
                                       UNITED STATES
                           SECURITIES AND EXCHANGE COMMISSION
                                 Washington, D.C.  20549


                                        FORM 8-K


                     Current Report Pursuant To Section 13 or 15(d) of
                            the Securities Exchange Act of 1934

           Date of Report (Date of earliest event reported):  December 27, 2005
                          (Date of earliest event reported)

            Indymac MBS, Inc. (as Depositor under the Pooling and Servicing
                Agreement, dated as September 1, 2005, providing for the
               issuance of IndyMac INDX Mortgage Loan Trust 2005-AR18
                Mortgage Pass-Through Certificates, Series 2005-AR18)
                 (Exact name of registrant as specified in charter)


                                         DELAWARE
                     (State or Other Jurisdiction of Incorporation)

               333-127556-04                         95-4791925
          (Commission File Number)        (I.R.S. Employer Identification No.)


          155 NORTH LAKE AVENUE
          PASADENA, CALIFORNIA                         91101
          (Address of principal executive offices)     (Zip Code)



          Registrant's Telephone Number, Including Area Code:  (800) 669-2300

       (Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any
of the following provisions (see General Instruction A.2. below):

[  ] Written communications pursuant to Rule 425 under the Securities Act
(17 CFR 230.425)

[  ] Soliciting material pursuant to Rule 14a-12(b) under the Exchange Act
(17 CFR 240.14a-12(b))

[  ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
Exchange Act (17 CFR 240.14d-2(b))

[  ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
Exchange Act (17 CFR 240.13e-4(c))


     Item 8.01  Other Events

     Attached hereto is a copy of the Monthly Remittance Statements to the
     Certificateholders which was derived from the monthly information
     submitted by the Master Servicer of the Trust to the Trustee.


     Item 9.01 Financial Statements and Exhibits

     (c) Exhibits:

     Exhibit No. Description

     99.1 Monthly Remittance Statement to the Certificateholders dated as of
     December 27, 2005.

                                    Signatures

               Pursuant to the requirements of the Securities Exchange Act of
          1934, the Registrant has duly caused this report to be signed on its
          behalf by the undersigned, hereunto duly authorized.


                                  Deutsche Bank National Trust Company,
                                  in its capacity as Trustee under the
                                  Pooling and Servicing Agreement on
                                  behalf of Indymac MBS, Inc., Registrant


          Date:  Dec 29, 2005               By:  /s/  Katherine M. Wannenmacher
                                            Katherine M. Wannenmacher
                                            Vice President


                                   EXHIBIT INDEX

          DOCUMENT

          99.1 Monthly Remittance Statement to the Certificateholders
          dated as of December 27, 2005.



IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

				External Parties						Table of Contents

													Page
				Seller
										1. Certificate Payment Report					2
				IndyMac Bank
										2. Collection Account Report					8

										3. Credit Enhancement Report					10
										4. Collateral Report					11
				Certificate Insurer(s)						5. Delinquency Report					14

										6. REO Report					17

										7. Foreclosure Report					18
										8. Prepayment Report					19
										9. Prepayment Detail Report					22

										10. Realized Loss Report					25
										11. Realized Loss Detail Report					28
				Servicer(s)
										12. Triggers and Adj. Cert. Report					29
				IndyMac Bank
										13. Other Related Information					30



				Underwriter(s)
				Goldman Sachs & Co.


										Total Number of Pages					30


				Dates						Contacts

				Cut-Off Date:			September 01, 2005			Brent Hoyler
				Close Date:			September 07, 2005			Administrator
				First Distribution Date:			October 25, 2005			(714) 247-6322
										Brent.Hoyler@db.com

										Address:
										1761 East St. Andrew Place, Santa Ana, CA 92705
				Distribution Date:			December 27, 2005
										Factor Information:			(800) 735-7777
				Record Date:			November 30, 2005
										Main Phone Number:			(714) 247-6000

							December 23, 2005


										https://www.tss.db.com/invr






Page 1 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Certificate Payment Report
Current Period Distribution - REMIC IV
					Prior												Current
	Class		Original		Principal						Total		Realized		Deferred		Principal

Class	Type	Cur	Face Value		Balance		Interest		Principal		Distribution		Loss		Interest		Balance


					(1)		(2)		(3)		(4)=(2)+(3)		(5)		(6)		(7)=(1)-(3)-(5)+(6)

1-A-1	FLT	$	629,654,000.00		620,987,407.98		2,484,639.62		6,570,513.48		9,055,153.10		0.00		0.00		614,416,894.50

1-A-2	FLT	$	262,356,000.00		258,744,917.69		1,150,264.91		2,737,715.69		3,887,980.60		0.00		0.00		256,007,202.00
1-A-3A	FLT	$	77,413,000.00		76,347,483.24		314,297.14		807,813.75		1,122,110.89		0.00		0.00		75,539,669.49
1-A-3B	FLT	$	80,000,000.00		78,898,875.64		317,787.14		834,809.40		1,152,596.54		0.00		0.00		78,064,066.24
2-A-1A	FLT	$	398,032,000.00		389,662,190.58		1,559,081.72		5,018,486.46		6,577,568.18		0.00		0.00		384,643,704.12
2-A-1B	FLT	$	300,000,000.00		293,691,605.64		1,297,790.57		3,782,474.62		5,080,265.19		0.00		0.00		289,909,131.02
2-A-2A	FLT	$	50,000,000.00		48,948,600.94		198,894.48		630,412.44		829,306.92		0.00		0.00		48,318,188.50
2-A-2B	FLT	$	65,846,000.00		64,461,391.55		245,114.44		830,202.75		1,075,317.19		0.00		0.00		63,631,188.80
2-A-2C	FLT	$	175,000,000.00		171,320,103.29		731,156.13		2,206,443.53		2,937,599.66		0.00		0.00		169,113,659.76
2-A-3A	FLT	$	84,508,000.00		82,730,967.36		340,575.82		1,065,497.88		1,406,073.70		0.00		0.00		81,665,469.48
2-A-3B	FLT	$	90,000,000.00		88,107,481.70		354,877.36		1,134,742.39		1,489,619.75		0.00		0.00		86,972,739.31
1-X	CSTR	$	0.00		0.00		759,178.08		0.00		759,178.08		0.00		0.00		0.00
2-X	CSTR	$	0.00		0.00		648,431.82		0.00		648,431.82		0.00		0.00		0.00
A-R	R	$	100.00		0.00		0.01		0.00		0.01		0.00		0.00		0.00
B-1	SUB	$	12,201,000.00		12,185,157.50		51,678.61		1,249.78		52,928.39		0.00		0.00		12,183,907.72
B-2	SUB	$	49,300,000.00		49,235,985.94		211,003.55		5,049.93		216,053.48		0.00		0.00		49,230,936.01
B-3	SUB	$	33,764,000.00		33,720,158.81		152,002.98		3,458.54		155,461.52		0.00		0.00		33,716,700.27
B-4	SUB	$	14,470,000.00		14,451,211.29		65,913.58		1,482.20		67,395.78		0.00		0.00		14,449,729.09
B-5	SUB	$	13,264,000.00		13,246,777.23		62,068.51		1,358.67		63,427.18		0.00		0.00		13,245,418.56
B-6	SUB	$	10,853,000.00		10,838,907.82		52,424.18		1,111.70		53,535.88		0.00		0.00		10,837,796.12
B-7	SUB	$	9,647,000.00		9,634,473.76		46,598.74		988.17		47,586.91		0.00		0.00		9,633,485.59
B-8	SUB	$	7,235,000.00		7,225,605.64		34,947.85		741.10		35,688.95		0.00		0.00		7,224,864.54
B-9	SUB	$	16,882,000.00		16,860,079.41		81,546.58		1,729.27		83,275.85		0.00		0.00		16,858,350.14
B-10	SUB	$	18,088,000.00		18,064,513.46		87,372.03		1,852.80		89,224.83		0.00		0.00		18,062,660.66
B-11	SUB	$	13,269,015.79		13,251,786.49		64,094.47		1,359.18		65,453.65		0.01		0.00		13,250,427.30
B-X	CSTR	$	0.00		0.00		42,501.00		0.00		42,501.00		0.00		0.00		0.00
P-1	SUB	$	100.00		100.00		181,355.54		0.00		181,355.54		0.00		0.00		100.00
P-2	SUB	$	100.00		100.00		176,532.01		0.00		176,532.01		0.00		0.00		100.00


Total			2,411,782,315.79		2,372,615,882.96		11,712,128.87		25,639,493.73		37,351,622.60		0.01		0.00		2,346,976,389.22






Page 2 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Interest Accrual Detail Current Period Factor Information per $1,000 of Original Face-
									Orig. Principal		Prior							Current

	Period		Period						(with Notional)		Principal						Total	Principal

Class	Starting		Ending		Method		Cusip		Balance		Balance		Interest		Principal		Distribution	Balance

									(1)		(1)		(2)		(3)		(4)=(2)+(3)	(5)
1-A-1	11/25/05		12/26/05		A-Act/360		45660LVZ9		629,654,000.00		986.235945		3.946040		10.435118		14.381157	975.800828
1-A-2	11/25/05		12/26/05		A-Act/360		45660LWA3		262,356,000.00		986.235945		4.384367		10.435118		14.819484	975.800828
1-A-3A	11/25/05		12/26/05		A-Act/360		45660LWB1		77,413,000.00		986.235945		4.060005		10.435117		14.495122	975.800828
1-A-3B	11/25/05		12/26/05		A-Act/360		45660LWC9		80,000,000.00		986.235946		3.972339		10.435118		14.407457	975.800828
2-A-1A	11/25/05		12/26/05		A-Act/360		45660LWD7		398,032,000.00		978.972019		3.916976		12.608249		16.525225	966.363770
2-A-1B	11/25/05		12/26/05		A-Act/360		45660LWE5		300,000,000.00		978.972019		4.325969		12.608249		16.934217	966.363770
2-A-2A	11/25/05		12/26/05		A-Act/360		45660LWV7		50,000,000.00		978.972019		3.977890		12.608249		16.586138	966.363770
2-A-2B	11/01/05		11/30/05		A-30/360		45660LWW5		65,846,000.00		978.972019		3.722541		12.608249		16.330790	966.363770
2-A-2C	11/25/05		12/26/05		A-Act/360		45660LWF2		175,000,000.00		978.972019		4.178035		12.608249		16.786284	966.363770
2-A-3A	11/25/05		12/26/05		A-Act/360		45660LWG0		84,508,000.00		978.972019		4.030102		12.608249		16.638350	966.363770
2-A-3B	11/25/05		12/26/05		A-Act/360		45660LWH8		90,000,000.00		978.972019		3.943082		12.608249		16.551331	966.363770
1-X	11/01/05		11/30/05		A-30/360		45660LWS4		0.00		0.000000		0.000000		0.000000		0.000000	0.000000
2-X	11/01/05		11/30/05		A-30/360		45660LWT2		0.00		0.000000		0.000000		0.000000		0.000000	0.000000
A-R	11/01/05		11/30/05		A-30/360		45660LYT0		100.00		0.000000		0.100000		0.000000		0.100000	0.000000
B-1	11/25/05		12/26/05		A-Act/360		45660LWJ4		12,201,000.00		998.701541		4.235604		0.102433		4.338037	998.599108
B-2	11/25/05		12/26/05		A-Act/360		45660LWK1		49,300,000.00		998.701540		4.279991		0.102433		4.382424	998.599108
B-3	11/25/05		12/26/05		A-Act/360		45660LWL9		33,764,000.00		998.701540		4.501925		0.102433		4.604357	998.599108
B-4	11/25/05		12/26/05		A-Act/360		45660LWM7		14,470,000.00		998.701540		4.555189		0.102433		4.657621	998.599108
B-5	11/25/05		12/26/05		A-Act/360		45660LWN5		13,264,000.00		998.701540		4.679472		0.102433		4.781904	998.599107
B-6	11/25/05		12/26/05		A-Act/360		45660LWP0		10,853,000.00		998.701541		4.830386		0.102433		4.932819	998.599108
B-7	11/25/05		12/26/05		A-Act/360		45660LWQ8		9,647,000.00		998.701540		4.830387		0.102433		4.932820	998.599107
B-8	11/25/05		12/26/05		A-Act/360		45660LWR6		7,235,000.00		998.701540		4.830387		0.102433		4.932820	998.599107
B-9	11/25/05		12/26/05		A-Act/360		45660LWX3		16,882,000.00		998.701541		4.830386		0.102433		4.932819	998.599108
B-10	11/25/05		12/26/05		A-Act/360		45660LWY1		18,088,000.00		998.701540		4.830386		0.102433		4.932819	998.599108
B-11	11/25/05		12/26/05		A-Act/360		45660LWZ8		13,269,015.79		998.701539		4.830386		0.102433		4.932819	998.599106
B-X	11/01/05		11/30/05		A-30/360		45660LWU9		0.00		0.000000		0.000000		0.000000		0.000000	0.000000
P-1	11/25/05		12/24/05		A-30/360		45660LYU7		100.00		1,000.000000		1,813,555.400000		0.000000		1,813,555.400000	1,000.000000
P-2	11/25/05		12/24/05		A-30/360		45660LYV5		100.00		1,000.000000		1,765,320.100000		0.000000		1,765,320.100000	1,000.000000




Page 3 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Distribution to Date - REMIC IV
																	Current


	Original				Unscheduled		Scheduled		Total		Total		Realized		Deferred		Principal

Class	Face Value		Interest		Principal		Principal		Principal		Distribution		Loss		Interest		Balance
	(1)		(2)		(3)		(4)		(5)=(3)+(4)		(6)=(2)+(5)		(7)		(8)		(9)=(1)-(5)-(7)+(8)
1-A-1	629,654,000.00		8,179,888.50		14,176,290.12		1,060,815.38		15,237,105.50		23,416,994.00		0.00		0.00		614,416,894.50
1-A-2	262,356,000.00		3,810,209.97		5,906,791.31		442,006.69		6,348,798.00		10,159,007.97		0.00		0.00		256,007,202.00
1-A-3A	77,413,000.00		1,036,513.34		1,742,908.25		130,422.26		1,873,330.51		2,909,843.85		0.00		0.00		75,539,669.49
1-A-3B	80,000,000.00		1,046,640.23		1,801,153.02		134,780.74		1,935,933.76		2,982,573.99		0.00		0.00		78,064,066.24
2-A-1A	398,032,000.00		5,157,612.39		12,933,591.08		454,704.80		13,388,295.88		18,545,908.27		0.00		0.00		384,643,704.12
2-A-1B	300,000,000.00		4,318,302.02		9,748,154.22		342,714.76		10,090,868.98		14,409,171.00		0.00		0.00		289,909,131.02
2-A-2A	50,000,000.00		658,586.93		1,624,692.37		57,119.13		1,681,811.50		2,340,398.43		0.00		0.00		48,318,188.50
2-A-2B	65,846,000.00		719,328.45		2,139,589.88		75,221.32		2,214,811.20		2,934,139.65		0.00		0.00		63,631,188.80
2-A-2C	175,000,000.00		2,428,078.52		5,686,423.30		199,916.94		5,886,340.24		8,314,418.76		0.00		0.00		169,113,659.76
2-A-3A	84,508,000.00		1,128,615.23		2,745,990.06		96,540.46		2,842,530.52		3,971,145.75		0.00		0.00		81,665,469.48
2-A-3B	90,000,000.00		1,174,453.06		2,924,446.26		102,814.43		3,027,260.69		4,201,713.75		0.00		0.00		86,972,739.31
1-X	0.00		1,669,045.41		0.00		0.00		0.00		1,669,045.41		0.00		0.00		0.00
2-X	0.00		1,450,522.04		0.00		0.00		0.00		1,450,522.04		0.00		0.00		0.00
A-R	100.00		138,549.39		82.31		17.69		100.00		138,649.39		0.00		0.00		0.00
B-1	12,201,000.00		169,583.39		0.00		17,092.28		17,092.28		186,675.67		0.00		0.00		12,183,907.72
B-2	49,300,000.00		692,822.30		0.00		69,063.99		69,063.99		761,886.29		0.00		0.00		49,230,936.01
B-3	33,764,000.00		500,499.18		0.00		47,299.73		47,299.73		547,798.91		0.00		0.00		33,716,700.27
B-4	14,470,000.00		217,170.39		0.00		20,270.91		20,270.91		237,441.30		0.00		0.00		14,449,729.09
B-5	13,264,000.00		204,791.77		0.00		18,581.44		18,581.44		223,373.21		0.00		0.00		13,245,418.56
B-6	10,853,000.00		173,251.31		0.00		15,203.88		15,203.88		188,455.19		0.00		0.00		10,837,796.12
B-7	9,647,000.00		145,280.42		0.00		13,514.41		13,514.41		158,794.83		0.00		0.00		9,633,485.59
B-8	7,235,000.00		96,398.33		0.00		10,135.46		10,135.46		106,533.79		0.00		0.00		7,224,864.54
B-9	16,882,000.00		224,933.86		0.00		23,649.86		23,649.86		248,583.72		0.00		0.00		16,858,350.14
B-10	18,088,000.00		241,002.48		0.00		25,339.34		25,339.34		266,341.82		0.00		0.00		18,062,660.66
B-11	13,269,015.79		176,794.87		0.00		18,588.46		18,588.46		195,383.33		0.02		0.00		13,250,427.30
B-X	0.00		114,967.66		0.00		0.00		0.00		114,967.66		0.00		0.00		0.00
P-1	100.00		374,145.10		0.00		0.00		0.00		374,145.10		0.00		0.00		100.00
P-2	100.00		313,086.72		0.00		0.00		0.00		313,086.72		0.00		0.00		100.00


Total	2,411,782,315.79		36,561,073.26		61,430,112.18		3,375,814.36		64,805,926.54		101,366,999.80		0.02		0.00		2,346,976,389.22



Page 4 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Interest Detail - REMIC IV
	Pass		Prior Principal				Non-		Prior		Unscheduled				Paid or		Current


	Through		(with Notional)		Accrued		Supported		Unpaid		Interest		Optimal		Deferred		Unpaid

Class	Rate		Balance		Interest		Interest SF		Interest		Adjustment		Interest		Interest		Interest
					(1)		(2)		(3)		(4)		(5)=(1)-(2)+(3)+(4)		(6)		(7)=(5)-(6)
1-A-1	4.50125%		620,987,407.98		2,484,639.62		0.00		0.00		0.00		2,484,639.62		2,484,639.62		0.00
1-A-2	5.00125%		258,744,917.69		1,150,264.91		0.00		0.00		0.00		1,150,264.91		1,150,264.91		0.00
1-A-3A	4.63125%		76,347,483.24		314,297.14		0.00		0.00		0.00		314,297.14		314,297.14		0.00
1-A-3B	4.53125%		78,898,875.64		317,787.14		0.00		0.00		0.00		317,787.14		317,787.14		0.00
2-A-1A	4.50125%		389,662,190.58		1,559,081.72		0.00		0.00		0.00		1,559,081.72		1,559,081.72		0.00
2-A-1B	4.97125%		293,691,605.64		1,297,790.57		0.00		0.00		0.00		1,297,790.57		1,297,790.57		0.00
2-A-2A	4.57125%		48,948,600.94		198,894.48		0.00		0.00		0.00		198,894.48		198,894.48		0.00
2-A-2B	4.56300%		64,461,391.55		245,114.44		0.00		0.00		0.00		245,114.44		245,114.44		0.00
2-A-2C	4.80125%		171,320,103.29		731,156.13		0.00		0.00		0.00		731,156.13		731,156.13		0.00
2-A-3A	4.63125%		82,730,967.36		340,575.82		0.00		0.00		0.00		340,575.82		340,575.82		0.00
2-A-3B	4.53125%		88,107,481.70		354,877.36		0.00		0.00		0.00		354,877.36		354,877.36		0.00
1-X	0.00000%		0.00		759,178.08		0.00		0.00		0.00		759,178.08		759,178.08		0.00
2-X	0.00000%		0.00		648,431.82		0.00		0.00		0.00		648,431.82		648,431.82		0.00
A-R	0.00000%		0.00		0.00		0.00		0.00		0.00		0.00		0.01		0.00
B-1	4.77125%		12,185,157.50		51,678.61		0.00		0.00		0.00		51,678.61		51,678.61		0.00
B-2	4.82125%		49,235,985.94		211,003.55		0.00		0.00		0.00		211,003.55		211,003.55		0.00
B-3	5.07125%		33,720,158.81		152,002.98		0.00		0.00		0.00		152,002.98		152,002.98		0.00
B-4	5.13125%		14,451,211.29		65,913.58		0.00		0.00		0.00		65,913.58		65,913.58		0.00
B-5	5.27125%		13,246,777.23		62,068.51		0.00		0.00		0.00		62,068.51		62,068.51		0.00
B-6	5.44125%		10,838,907.82		52,424.18		0.00		0.00		0.00		52,424.18		52,424.18		0.00
B-7	5.44125%		9,634,473.76		46,598.74		0.00		0.00		0.00		46,598.74		46,598.74		0.00
B-8	5.44125%		7,225,605.64		34,947.85		0.00		0.00		0.00		34,947.85		34,947.85		0.00
B-9	5.44125%		16,860,079.41		81,546.58		0.00		0.00		0.00		81,546.58		81,546.58		0.00
B-10	5.44125%		18,064,513.46		87,372.03		0.00		0.00		0.00		87,372.03		87,372.03		0.00
B-11	5.44125%		13,251,786.49		64,094.47		0.00		0.00		0.00		64,094.47		64,094.47		0.00
B-X	0.00000%		0.00		42,501.00		0.00		0.00		0.00		42,501.00		42,501.00		0.00
P-1	0.00000%		100.00		0.00		0.00		0.00		0.00		0.00		181,355.54		0.00
P-2	0.00000%		100.00		0.00		0.00		0.00		0.00		0.00		176,532.01		0.00


Total			2,372,615,882.96		11,354,241.31		0.00		0.00		0.00		11,354,241.31		11,712,128.87		0.00



Page 5 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Current Period Distribution - REMIC IV
					Prior												Current
	Class		Original		Principal						Total		Realized		Deferred		Principal

Class	Type	Cur	Face Value		Balance		Interest		Principal		Distribution		Loss		Interest		Balance


					(1)		(2)		(3)		(4)=(2)+(3)		(5)		(6)		(7)=(1)-(3)-(5)+(6)

1-X-IO	CSTR	$	0.00		0.00		759,178.08		0.00		759,178.08		0.00		0.00		0.00

2-X-IO	CSTR	$	0.00		0.00		648,431.82		0.00		648,431.82		0.00		0.00		0.00
B-X-IO	CSTR	$	0.00		0.00		42,501.00		0.00		42,501.00		0.00		0.00		0.00
1-X-PO	CSTR	$	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
2-X-PO	CSTR	$	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
B-X-PO-1	CSTR	$	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
B-X-PO-2	CSTR	$	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00




Total			0.00		0.00		1,450,110.90		0.00		1,450,110.90		0.00		0.00		0.00





Interest Accrual Detail Current Period Factor Information per $1,000 of Original Face-
									Orig. Principal		Prior						Current

	Period		Period						(with Notional)		Principal						Total	Principal

Class	Starting		Ending		Method		Cusip		Balance		Balance		Interest		Principal		Distribution	Balance

									(1)		(1)		(2)		(3)		(4)=(2)+(3)	(5)
1-X-IO	11/01/05		11/30/05		A-30/360				1,049,423,000.00		986.235945		0.723424		0.000000		0.723424	975.800828
2-X-IO	11/01/05		11/30/05		A-30/360				1,163,386,000.00		978.972019		0.557366		0.000000		0.557366	966.363770
B-X-IO	11/01/05		11/30/05		A-30/360				198,973,015.00		998.701544		0.213602		0.000000		0.213602	998.599112
1-X-PO	11/01/05		11/30/05		A-30/360				0.00		0.000000		0.000000		0.000000		0.000000	0.000000
2-X-PO	11/01/05		11/30/05		A-30/360				0.00		0.000000		0.000000		0.000000		0.000000	0.000000
B-X-PO-1	11/01/05		11/30/05		A-30/360				0.00		0.000000		0.000000		0.000000		0.000000	0.000000
B-X-PO-2	11/01/05		11/30/05		A-30/360				0.00		0.000000		0.000000		0.000000		0.000000	0.000000






Page 6 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Distribution to Date - REMIC IV
																	Current


	Original				Unscheduled		Scheduled		Total		Total		Realized		Deferred		Principal

Class	Face Value		Interest		Principal		Principal		Principal		Distribution		Loss		Interest		Balance
	(1)		(2)		(3)		(4)		(5)=(3)+(4)		(6)=(2)+(5)		(7)		(8)		(9)=(1)-(5)-(7)+(8)
1-X-IO	0.00		1,669,024.81		0.00		0.00		0.00		1,669,045.41		0.00		0.00		0.00
2-X-IO	0.00		1,450,522.04		0.00		0.00		0.00		1,450,522.04		0.00		0.00		0.00
B-X-IO	0.00		114,967.64		0.00		0.00		0.00		114,967.64		0.00		0.00		0.00
1-X-PO	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
2-X-PO	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
B-X-PO-1	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
B-X-PO-2	0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00




Total	0.00		3,234,514.49		0.00		0.00		0.00		3,234,535.09		0.00		0.00		0.00


Interest Detail - REMIC IV
	Pass		Prior Principal				Non-		Prior		Unscheduled				Paid or		Current


	Through		(with Notional)		Accrued		Supported		Unpaid		Interest		Optimal		Deferred		Unpaid

Class	Rate		Balance		Interest		Interest SF		Interest		Adjustment		Interest		Interest		Interest
				(1)		(2)		(3)		(4)		(5)=(1)-(2)+(3)+(4)		(6)		(7)=(5)-(6)
1-X-IO	0.88022%		1,034,978,684.55		759,178.08		0.00		0.00		0.00		759,178.08		759,178.08		0.00
2-X-IO	0.68321%		1,138,922,341.06		648,431.82		0.00		0.00		0.00		648,431.82		648,431.82		0.00
B-X-IO	0.25666%		198,714,657.35		42,501.00		0.00		0.00		0.00		42,501.00		42,501.00		0.00
1-X-PO	0.00000%		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
2-X-PO	0.00000%		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
B-X-PO-1	0.00000%		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00
B-X-PO-2	0.00000%		0.00		0.00		0.00		0.00		0.00		0.00		0.00		0.00




Total			2,372,615,682.96		1,450,110.90		0.00		0.00		0.00		1,450,110.90		1,450,110.90		0.00



Page 7 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Collection Account Report
SUMMARY

										Group 2		Group 1		Total
Principal Collections										14,668,260.07		10,971,233.67		25,639,493.74
Principal Withrawals										0.00		0.00		0.00
Principal Other Accounts										0.00		0.00		0.00
TOTAL NET PRINCIPAL										14,668,260.07		10,971,233.67		25,639,493.74
Interest Collections										5,969,487.53		5,588,260.22		11,557,747.75
Interest Withdrawals										-0.00		-0.00		-0.00
Interest Other Accounts										176,532.01		181,355.54		357,887.55
Interest Fees										-91,800.22		-96,861.21		-203,506.44
TOTAL NET INTEREST										6,054,219.32		5,672,754.55		11,712,128.86
TOTAL AVAILABLE FUNDS FOR DISTRIBUTION										20,722,479.39		16,643,988.22		37,351,622.60



PRINCIPAL - COLLECTIONS

											Group 2		Group 1		Total
Scheduled Principal Received											0.00		214.45		214.45
Curtailments											(1,551,844.61)		(1,577,555.20)		(3,129,399.81)
Prepayments In Full											16,220,104.68		12,304,534.12		28,524,638.80
Repurchased/Substitutions											0.00		244,040.30		244,040.30
Liquidations											0.00		0.00		0.00
Insurance Principal											0.00		0.00		0.00
Other Additional Principal											0.00		0.00		0.00
Delinquent Principal											-0.00		-214.45		-214.45
Realized Losses											-0.00		-0.00		-0.00
Advanced Principal											0.00		214.45		214.45
TOTAL PRINCIPAL COLLECTED											14,668,260.07		10,971,233.67		25,639,493.74


PRINCIPAL - WITHDRAWALS

SPACE INTENTIONALLY LEFT BLANK



PRINCIPAL - OTHER ACCOUNTS

										Group 2		Group 1		Total
TOTAL PRINCIPAL OTHER ACCOUNTS										0.00		0.00		0.00





Page 8 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

INTEREST - COLLECTIONS

										Group 2		Group 1		Total
Scheduled Interest										6,266,771.94		5,843,471.68		12,110,243.62
Repurchased/Substitution Interest										0.00		1,273.69		1,273.69
Liquidation Interest										0.00		0.00		0.00
Insurance Interest										0.00		0.00		0.00
Other Additional Interest										0.00		0.00		0.00
Prepayment Interest Shortfalls										-8,230.52		-9,251.68		-17,482.20
Delinquent Interest										-4,798,786.80		-4,252,274.74		-9,051,061.54
Compensating Interest										8,230.52		9,251.68		17,482.20
Civil Relief Act Shortfalls										-0.00		-0.00		-0.00
Interest Advanced										4,501,502.39		3,995,789.59		8,497,291.98
TOTAL INTEREST COLLECTED										5,969,487.53		5,588,260.22		11,557,747.75


INTEREST - WITHDRAWALS

										Group 2		Group 1		Total
TOTAL INTEREST WITHDRAWALS										0.00		0.00		0.00



INTEREST - OTHER ACCOUNTS

										Group 2		Group 1		Total
Prepayment Charges										176,532.01		181,355.54		357,887.55
Capitalized Interest														0.00
BONY Class 1-A-1, 1-A-2, 1-A-3A & 1-A-3B Cap Payment														0.00
BONY Class 2-A-1A, 2-A-1B,2-A-2A, 2-A-2C, 2-A-3A, &														0.00
TOTAL INTEREST OTHER ACCOUNTS										176,532.01		181,355.54		357,887.55



INTEREST - FEES

										Group 2		Group 1		Total
Current Servicing Fees										91,282.13		96,390.71		187,672.84
Class 1-A-3B Ambac Premium														7,013.23
Class 2-A-3B Ambac Premium														7,831.78
Trustee Fees										518.09		470.50		988.59
TOTAL INTEREST FEES										91,800.22		96,861.21		203,506.44




Page 9 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Credit Enhancement Report
ACCOUNTS

SPACE INTENTIONALLY LEFT BLANK



INSURANCE

										Group 2		Group 1		Total
Class 1-A-3B Ambac Premium														7,013.23
Class 2-A-3B Ambac Premium														7,831.78



STRUCTURAL FEATURES

SPACE INTENTIONALLY LEFT BLANK




Page 10 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Collateral Report


COLLATERAL



											Group 2		Group 1		Total



Loan Count:


Original										2,555		4,879		7,434
Prior										2,502		4,807		7,309
Prefunding										0		0		0
Scheduled Paid Offs										-0		-0		-0
Full Voluntary Prepayments										-31		-54		-85
Repurchases										-0		-1		-1
Liquidations										-0		-0		-0
Current										2,471		4,752		7,223
Principal Balance:


Original										1,267,996,081.81		1,143,786,033.97		2,411,782,115.78
Prior										1,243,412,914.59		1,129,202,768.37		2,372,615,682.96
Prefunding										0.00		0.00		0.00
Scheduled Principal										-0.00		-214.45		-214.45
Partial Prepayments										(1,551,844.61)		(1,577,555.20)		(3,129,399.81)
Full Voluntary Prepayments										-16,220,104.68		-12,304,534.12		-28,524,638.80
Repurchases										-0.00		-244,040.30		-244,040.30
Liquidations										-0.00		-0.00		-0.00
Current										1,228,744,654.52		1,118,231,534.70		2,346,976,189.22





PREFUNDING

SPACE INTENTIONALLY LEFT BLANK






Page 11 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

CHARACTERISTICS

										Group 2		Group 1		Total
Weighted Average Coupon Original										5.06001%		4.91730%		4.99233%
Weighted Average Coupon Prior										5.89410%		6.06636%		5.97584%
Weighted Average Coupon Current										6.04797%		6.21115%		6.12564%
Weighted Average Months to Maturity Original										357		358		357
Weighted Average Months to Maturity Prior										356		357		357
Weighted Average Months to Maturity Current										355		356		356
Weighted Avg Remaining Amortization Term Original										357		358		357
Weighted Avg Remaining Amortization Term Prior										356		357		357
Weighted Avg Remaining Amortization Term Current										355		356		356
Weighted Average Seasoning Original										2.52		2.28		2.40
Weighted Average Seasoning Prior										3.51		3.28		3.40
Weighted Average Seasoning Current										4.51		4.27		4.40









Page 12 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

ARM CHARACTERISTICS

										Group 2		Group 1		Total
Weighted Average Margin Original										2.88392%		3.04715%		2.96133%
Weighted Average Margin Prior										2.88426%		3.04738%		2.96166%
Weighted Average Margin Current										2.88367%		3.04763%		2.96170%
Weighted Average Max Rate Original										9.08990%		8.92349%		9.01098%
Weighted Average Max Rate Prior										9.05617%		8.92344%		8.99319%
Weighted Average Max Rate Current										9.06039%		8.92351%		8.99525%
Weighted Average Min Rate Original										1.09215%		1.10615%		1.09879%
Weighted Average Min Rate Prior										1.09253%		1.10681%		1.09930%
Weighted Average Min Rate Current										1.09155%		1.10723%		1.09901%
Weighted Average Cap Up Original										96.13668%		97.88894%		96.96769%
Weighted Average Cap Up Prior										96.12632%		97.93300%		96.98360%
Weighted Average Cap Up Current										96.14066%		97.93948%		96.99677%
Weighted Average Cap Down Original										96.13668%		97.88894%		96.96769%
Weighted Average Cap Down Prior										96.12632%		97.93300%		96.98360%
Weighted Average Cap Down Current										96.14066%		97.93948%		96.99677%




SERVICING FEES & ADVANCES

											Group 2		Group 1		Total




Current Servicing Fees										91,282.13		96,390.71		187,672.84
Delinquent Servicing Fees										297,284.41		256,485.15		553,769.56
TOTAL SERVICING FEES										388,566.54		352,875.88		741,442.42


Total Servicing Fees										388,566.54		352,875.88		741,442.42
Compensating Interest										-8,230.52		-9,251.68		-17,482.20
Delinquent Servicing Fees										-297,284.41		-256,485.15		-553,769.56
COLLECTED SERVICING FEES										83,051.61		87,139.05		170,190.65


Total Advaced Interest										4,501,502.39		3,995,789.59		8,497,291.98
Total Advaced Principal										0.00		214.45		214.45
Aggregate Advances with respect to this Distribution										4,501,502.39		3,996,004.04		8,497,506.43





ADDITIONAL COLLATERAL INFORMATION
										Group 2		Group 1		Total
Prepayment Interest Shortfall (PPIS)										8,230.52		9,251.68		17,482.20
Compensating Interest										-8,230.52		-9,251.68		-17,482.20
Net Prepayment Interest Shortfall (PPIS)										0.00		0.00		0.00

Weighted Average Net Mortgage Rate										5.672472%		5.835691%		5.750153%

Current Deferred Interest										2,253,452.24		2,169,088.40		4,422,540.64
Cumulative Deferred Interest										2,253,452.24		2,169,088.40		4,422,540.64
Current Net Deferred Interest										0.00		0.00		0.00
Cumulative Net Deferred Interest										0.00		0.00		0.00



Page 13 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Delinquency Report

	TOTAL
					< 1 PAYMENT		1 PAYMENT		2 PAYMENTS		3+ PAYMENTS		TOTAL
	DELINQUENT		Balance				27,954,508.23		3,917,470.81		1,217,412.84		33,089,391.88
			% Balance				1.19%		0.17%		0.05%		1.41%
			# Loans				93		19		4		116
			% # Loans				1.29%		0.26%		0.06%		1.61%
	FORECLOSURE		Balance		0.00		0.00		0.00		0.00		0.00
			% Balance		0.00%		0.00%		0.00%		0.00%		0.00%
			# Loans		0		0		0		0		0
			% # Loans		0.00%		0.00%		0.00%		0.00%		0.00%
	BANKRUPTCY		Balance		1,270,203.56		0.00		238,155.90		0.00		1,508,359.46
			% Balance		0.05%		0.00%		0.01%		0.00%		0.06%
			# Loans		4		0		1		0		5
			% # Loans		0.06%		0.00%		0.01%		0.00%		0.07%
	REO		Balance		0.00		0.00		0.00		0.00		0.00
			% Balance		0.00%		0.00%		0.00%		0.00%		0.00%
			# Loans		0		0		0		0		0
			% # Loans		0.00%		0.00%		0.00%		0.00%		0.00%
	TOTAL		Balance		1,270,203.56		27,954,508.23		4,155,626.71		1,217,412.84		34,597,751.34
			% Balance		0.05%		1.19%		0.18%		0.05%		1.47%
			# Loans		4		93		20		4		121
			% # Loans		0.06%		1.29%		0.28%		0.06%		1.68%








Page 14 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution


	GROUP 1
					< 1 PAYMENT		1 PAYMENT		2 PAYMENTS		3+ PAYMENTS		TOTAL
	DELINQUENT		Balance				15,419,072.96		3,535,796.63		715,725.91		19,670,595.50
			% Balance				1.38%		0.32%		0.06%		1.76%
			# Loans				67		18		3		88
			% # Loans				1.41%		0.38%		0.06%		1.85%
	FORECLOSURE		Balance		0.00		0.00		0.00		0.00		0.00
			% Balance		0.00%		0.00%		0.00%		0.00%		0.00%
			# Loans		0		0		0		0		0
			% # Loans		0.00%		0.00%		0.00%		0.00%		0.00%
	BANKRUPTCY		Balance		661,496.34		0.00		238,155.90		0.00		899,652.24
			% Balance		0.06%		0.00%		0.02%		0.00%		0.08%
			# Loans		3		0		1		0		4
			% # Loans		0.06%		0.00%		0.02%		0.00%		0.08%
	REO		Balance		0.00		0.00		0.00		0.00		0.00
			% Balance		0.00%		0.00%		0.00%		0.00%		0.00%
			# Loans		0		0		0		0		0
			% # Loans		0.00%		0.00%		0.00%		0.00%		0.00%
	TOTAL		Balance		661,496.34		15,419,072.96		3,773,952.53		715,725.91		20,570,247.74
			% Balance		0.06%		1.38%		0.34%		0.06%		1.84%
			# Loans		3		67		19		3		92
			% # Loans		0.06%		1.41%		0.40%		0.06%		1.94%










Page 15 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

	GROUP 2
					< 1 PAYMENT		1 PAYMENT		2 PAYMENTS		3+ PAYMENTS		TOTAL
	DELINQUENT		Balance				12,535,435.27		381,674.18		501,686.93		13,418,796.38
			% Balance				1.02%		0.03%		0.04%		1.09%
			# Loans				26		1		1		28
			% # Loans				1.05%		0.04%		0.04%		1.13%
	FORECLOSURE		Balance		0.00		0.00		0.00		0.00		0.00
			% Balance		0.00%		0.00%		0.00%		0.00%		0.00%
			# Loans		0		0		0		0		0
			% # Loans		0.00%		0.00%		0.00%		0.00%		0.00%
	BANKRUPTCY		Balance		608,707.22		0.00		0.00		0.00		608,707.22
			% Balance		0.05%		0.00%		0.00%		0.00%		0.05%
			# Loans		1		0		0		0		1
			% # Loans		0.04%		0.00%		0.00%		0.00%		0.04%
	REO		Balance		0.00		0.00		0.00		0.00		0.00
			% Balance		0.00%		0.00%		0.00%		0.00%		0.00%
			# Loans		0		0		0		0		0
			% # Loans		0.00%		0.00%		0.00%		0.00%		0.00%
	TOTAL		Balance		608,707.22		12,535,435.27		381,674.18		501,686.93		14,027,503.60
			% Balance		0.05%		1.02%		0.03%		0.04%		1.14%
			# Loans		1		26		1		1		29
			% # Loans		0.04%		1.05%		0.04%		0.04%		1.17%









Page 16 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
REO Report
Loan Number			Original		Stated				Current		State &

														First
&			Principal		Principal		Paid to		Note		LTV at		Original		Payment

Loan Group			Balance		Balance		Date		Rate		Origination		Term		Date




TOTAL


Page 17 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Foreclosure Report
Loan Number			Original		Stated				Current		State &

														First
&			Principal		Principal		Paid to		Note		LTV at		Original		Payment

Loan Group			Balance		Balance		Date		Rate		Origination		Term		Date




TOTAL


Page 18 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Prepayment Report

VOLUNTARY PREPAYMENTS


											Group 2		Group 1		Total




Current


Number of Paid in Full Loans										31		54		85
Number of Repurchased Loans										0		1		1
Total Number of Loans Prepaid in Full										31		55		86
Curtailments Amount										(1,551,844.61)		(1,577,555.20)		(3,129,399.81)
Paid in Full Balance										16,220,104.68		12,304,534.12		28,524,638.80
Repurchased Loans Balance										0.00		244,040.30		244,040.30
Total Prepayment Amount										14,668,260.07		10,971,019.22		25,639,279.29

Cumulative


Number of Paid in Full Loans										82		122		204
Number of Repurchased Loans										2		5		7
Total Number of Loans Prepaid in Full										84		127		211
Paid in Full Balance										43,082,622.10		28,571,389.68		71,654,011.78
Repurchased Loans Balance										1,011,000.00		1,378,277.41		2,389,277.41
Curtailments Amount										(5,279,734.93)		(4,944,164.66)		(10,223,899.59)
Total Prepayment Amount										38,813,887.17		25,005,502.43		63,819,389.60










Page 19 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

VOLUNTARY PREPAYMENTS RATES


											Group 2		Group 1		Total



SMM										1.18%		0.97%		1.08%
3 Months Avg SMM										1.03%		0.73%		0.89%
12 Months Avg SMM										1.03%		0.73%		0.89%
Avg SMM Since Cut-off										1.03%		0.73%		0.89%


CPR										13.27%		11.06%		12.22%
3 Months Avg CPR										11.70%		8.47%		10.18%
12 Months Avg CPR										11.70%		8.47%		10.18%
Avg CPR Since Cut-off										11.70%		8.47%		10.18%


PSA										1,471.85%		1,293.68%		1,390.21%
3 Months Avg PSA Approximation										1,665.45%		1,292.58%		1,496.85%
12 Months Avg PSA Approximation										1,665.45%		1,292.58%		1,496.85%
Avg PSA Since Cut-off Approximation										1,665.45%		1,292.58%		1,496.86%










Page 20 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution






PREPAYMENT CALCULATION METHODOLOGY

Single Monthly Mortality (SMM): (Voluntary partial and full prepayments + Repurchases + Liquidations )/(Beg Principal Balance - Sched Principal) Conditional Prepayment Rate (CPR): 1-((1-SMM)^12) PSA Standard Prepayment Model: CPR/(0.002min(30,WAS)) Average SMM over period between nth month and mth month (AvgSMMn,m): [(1-SMMn)(1-SMMn+1)...(1-SMMm)]^(1/months in period n,m) Conditional Prepayment Rate (CPR): 1-((1-SMM)^12) Average PSA Approximation over period between the nth month and mth month: AvgCPRn,m/(0.002*Avg WASn,m)) Average WASn,m: (min(30,WASn)+min(30,WASn+1)+...+min(30,WASm)/(number of months in the period n,m) Weighted Average Seasoning (WAS) Dates correspond to distribution dates. Note: Prepayment rates are calculated since deal issue date and include partial and full voluntary prepayments, liquidations, and repurchases.













Page 21 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Prepayment Detail Report
Prepayment Detail Report - Mortgage Loans Prepaid in Full During Current Distribution
Loan Number			Original							Current		State &		Type Prepayment		First


&		Loan	Principal		Prepayment			Prepayment		Note		LTV at		&		Payment

Loan Group		Status	Balance		Amount			Date		Rate		Origination		Original Term		Date

121017514 2			463,875.00		464,925.27			16-Nov-2005		6.013%		CA - 75.00%		Paid Off - 360		01-Aug-2005

121035759 1			225,000.00		225,792.68			01-Dec-2005		6.113%		CA - 75.00%		Paid Off - 360		01-May-2005
121204640 1			250,000.00		250,402.35			16-Nov-2005		6.263%		NJ - 56.18%		Paid Off - 360		01-Jul-2005
121303534 2			485,500.00		487,663.39			05-Dec-2005		5.875%		CA - 79.59%		Paid Off - 360		01-Jun-2005
121303910 1			255,000.00		255,993.58			15-Dec-2005		6.663%		CA - 75.00%		Paid Off - 360		01-Aug-2005
121330330 1			275,000.00		275,243.22			15-Dec-2005		6.413%		CA - 50.00%		Paid Off - 360		01-Sep-2005
121331475 1			201,000.00		201,177.75			15-Dec-2005		6.413%		CA - 60.00%		Paid Off - 360		01-Sep-2005
121331701 1			330,000.00		330,291.86			15-Dec-2005		6.413%		CA - 60.00%		Paid Off - 360		01-Sep-2005
121343912 1			178,500.00		178,253.93			29-Nov-2005		5.763%		IL - 70.83%		Paid Off - 360		01-Aug-2005
121353907 1			255,000.00		255,671.08			15-Dec-2005		6.163%		IL - 76.12%		Paid Off - 360		01-Aug-2005
121387006 2			397,600.00		398,799.66			01-Dec-2005		6.313%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121397867 1			307,200.00		307,478.12			14-Dec-2005		6.063%		MA - 80.00%		Paid Off - 360		01-Sep-2005
121403422 1			391,575.00		392,559.87			16-Nov-2005		6.113%		HI - 75.00%		Paid Off - 360		01-Aug-2005
121417623 1			258,750.00		259,660.70			06-Dec-2005		6.513%		NY - 75.00%		Paid Off - 360		01-Aug-2005
121436783 2			400,000.00		400,991.15			06-Dec-2005		6.113%		CA - 56.90%		Paid Off - 360		01-Aug-2005
121462801 2			412,000.00		412,338.66			22-Nov-2005		6.013%		NY - 80.00%		Paid Off - 360		01-Sep-2005
121468443 2			610,000.00		611,457.69			05-Dec-2005		6.063%		CA - 67.78%		Paid Off - 360		01-Aug-2005
121468476 1			217,250.00		217,314.80			21-Nov-2005		5.663%		AZ - 89.99%		Paid Off - 360		01-Aug-2005
121477179 1			183,400.00		183,541.04			13-Dec-2005		6.413%		CA - 70.00%		Paid Off - 360		01-Aug-2005
121485216 2			400,000.00		400,955.84			02-Dec-2005		6.063%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121495693 1			162,000.00		162,241.26			23-Nov-2005		6.413%		MA - 75.88%		Paid Off - 360		01-Sep-2005
121497981 2			648,000.00		647,479.40			21-Nov-2005		5.913%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121503645 1			138,400.00		138,684.42			06-Dec-2005		6.363%		FL - 80.00%		Paid Off - 360		01-Aug-2005
121510907 1			219,000.00		219,438.62			22-Nov-2005		6.213%		FL - 56.88%		Paid Off - 360		#######
121513775 1			322,200.00		322,456.19			22-Nov-2005		6.000%		VA - 90.00%		Paid Off - 360		01-May-2005
121516724 1			236,200.00		236,640.87			12-Dec-2005		5.863%		CA - 70.51%		Paid Off - 360		01-Aug-2005
121518026 2			450,000.00		451,131.80			05-Dec-2005		6.113%		CA - 75.00%		Paid Off - 360		01-Aug-2005
121522244 1			131,300.00		131,335.15			13-Dec-2005		6.063%		FL - 89.99%		Paid Off - 360		01-Sep-2005
121523692 1			225,000.00		225,509.43			22-Nov-2005		6.013%		CA - 56.96%		Paid Off - 360		01-Aug-2005
121529994 2			444,000.00		445,228.19			02-Dec-2005		6.213%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121532061 1			180,200.00		179,768.99			14-Dec-2005		6.213%		CA - 61.50%		Paid Off - 360		01-Aug-2005
121532181 1			174,600.00		175,039.16			09-Dec-2005		6.113%		WA - 80.00%		Paid Off - 360		01-Aug-2005
121537252 2			1,000,000.00		1,000,488.38			02-Dec-2005		5.813%		CA - 66.67%		Paid Off - 360		01-Sep-2005
121538997 2			583,000.00		584,685.87			22-Nov-2005		6.263%		CA - 74.74%		Paid Off - 360		01-Aug-2005
121544385 2			508,000.00		509,596.55			02-Dec-2005		6.363%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121545258 1			250,000.00		248,967.73			01-Dec-2005		6.413%		MD - 79.11%		Paid Off - 360		01-Aug-2005
121546901 1			273,750.00		274,575.96			16-Nov-2005		6.313%		VA - 75.00%		Paid Off - 360		01-Aug-2005
121548019 1			213,750.00		214,243.56			16-Nov-2005		6.513%		CA - 75.00%		Paid Off - 360		01-Aug-2005
121551139 2			399,000.00		400,103.72			02-Dec-2005		6.213%		CA - 58.94%		Paid Off - 360		01-Aug-2005
121565102 2			408,000.00		408,471.49			22-Nov-2005		6.213%		FL - 80.00%		Paid Off - 360		01-Sep-2005
121568260 1			218,400.00		219,086.40			30-Nov-2005		6.363%		CA - 80.00%		Paid Off - 360		01-Aug-2005


Page 22 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Prepayment Detail Report - Mortgage Loans Prepaid in Full During Current Distribution
Loan Number			Original							Current		State &		Type Prepayment		First


&		Loan	Principal		Prepayment			Prepayment		Note		LTV at		&		Payment

Loan Group		Status	Balance		Amount			Date		Rate		Origination		Original Term		Date

121573555 1			121,680.00		121,970.78			16-Nov-2005		6.063%		FL - 71.58%		Paid Off - 360		01-Aug-2005

121579518 1			306,000.00		306,758.57			16-Nov-2005		6.163%		NV - 80.00%		Paid Off - 360		01-Aug-2005
121580254 2			600,000.00		597,930.46			21-Nov-2005		6.213%		CA - 48.39%		Paid Off - 360		01-Aug-2005
121589389 1			180,368.00		178,895.17			08-Dec-2005		6.013%		NV - 65.00%		Paid Off - 360		01-Oct-2005
121592890 2			410,000.00		411,134.13			18-Nov-2005		6.213%		CA - 68.33%		Paid Off - 360		01-Aug-2005
121594737 1			213,750.00		214,252.82			21-Nov-2005		6.613%		CA - 75.00%		Paid Off - 360		01-Aug-2005
121597304 1			296,500.00		297,394.62			02-Dec-2005		6.313%		CA - 74.13%		Paid Off - 360		01-Aug-2005
121598556 1			173,400.00		173,528.08			06-Dec-2005		5.963%		FL - 66.69%		Paid Off - 360		01-Sep-2005
121600727 1			248,800.00		249,431.74			01-Dec-2005		6.125%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121601127 1			110,000.00		110,304.30			16-Nov-2005		6.213%		CA - 47.83%		Paid Off - 360		01-Aug-2005
121613720 2			375,000.00		375,601.21			02-Dec-2005		6.413%		CA - 72.12%		Paid Off - 360		01-Aug-2005
121627335 2			650,000.00		650,018.35			07-Dec-2005		6.413%		CA - 73.28%		Paid Off - 61		01-Aug-2005
121627404 1			340,000.00		340,336.20			23-Nov-2005		6.113%		MA - 56.67%		Paid Off - 360		01-Sep-2005
121628462 2			470,400.00		470,551.30			02-Dec-2005		5.713%		CA - 80.00%		Paid Off - 360		01-Sep-2005
121632731 1			98,800.00		98,897.69			12-Dec-2005		6.113%		FL - 80.00%		Paid Off - 360		01-Sep-2005
121635783 1			274,400.00		274,213.76			05-Dec-2005		6.063%		CA - 80.00%		Paid Off - 360		01-Oct-2005
121638679 2			468,000.00		468,462.77			14-Dec-2005		6.113%		CA - 80.00%		Paid Off - 360		01-Sep-2005
121657101 2			414,400.00		414,636.96			16-Nov-2005		5.863%		CA - 70.00%		Paid Off - 360		01-Sep-2005
121662956 1			150,000.00		149,558.42			29-Nov-2005		6.313%		FL - 62.50%		Paid Off - 360		01-Sep-2005
121672032 1			232,000.00		231,861.35			01-Dec-2005		6.563%		AZ - 80.00%		Paid Off - 360		01-Oct-2005
121674638 1			100,000.00		99,761.69			01-Dec-2005		6.013%		NJ - 29.41%		Paid Off - 360		01-Sep-2005
121682194 2			433,600.00		434,173.41			13-Dec-2005		6.313%		CA - 80.00%		Paid Off - 360		01-Sep-2005
121693210 2			820,000.00		815,847.31			22-Nov-2005		6.013%		CA - 64.98%		Paid Off - 360		01-Aug-2005
121697346 1			288,000.00		288,274.39			14-Dec-2005		6.113%		AZ - 80.00%		Paid Off - 360		01-Sep-2005
121698725 1			240,000.00		240,136.64			09-Dec-2005		6.213%		CA - 78.69%		Paid Off - 360		01-Sep-2005
121702427 1			320,000.00		319,681.73			16-Nov-2005		6.413%		CA - 63.37%		Paid Off - 360		01-Oct-2005
121705431 1			353,500.00		353,318.96			05-Dec-2005		6.413%		CA - 70.00%		Paid Off - 360		01-Oct-2005
121707640 1			160,000.00		160,184.91			30-Nov-2005		6.213%		NJ - 56.14%		Paid Off - 360		01-Sep-2005
121717132 1			234,000.00		234,493.16			21-Nov-2005		6.125%		CA - 52.00%		Paid Off - 360		01-Aug-2005
121717704 2			592,000.00		593,785.07			01-Dec-2005		6.375%		CA - 80.00%		Paid Off - 360		01-Aug-2005
121723098 2			450,000.00		449,254.68			08-Dec-2005		6.000%		CA - 75.00%		Paid Off - 360		01-Aug-2005
121761776 2			578,000.00		578,075.92			29-Nov-2005		5.663%		CA - 77.07%		Paid Off - 360		01-Aug-2005
121771133 1			241,600.00		241,818.74			17-Nov-2005		6.063%		CA - 80.00%		Paid Off - 360		01-Sep-2005
121781430 1			262,700.00		262,894.02			18-Nov-2005		5.963%		MD - 42.10%		Paid Off - 360		01-Sep-2005
121783075 2			483,300.00		483,434.45			06-Dec-2005		6.063%		AZ - 90.00%		Paid Off - 360		01-Sep-2005
121794134 1			180,000.00		179,888.00			30-Nov-2005		6.413%		FL - 79.65%		Paid Off - 360		01-Oct-2005
121809957 2			441,600.00		441,300.28			06-Dec-2005		6.063%		CA - 80.00%		Paid Off - 360		01-Oct-2005
121826265 1			166,500.00		166,647.25			23-Nov-2005		5.463%		ME - 60.77%		Paid Off - 360		01-Aug-2005
121828452 2			520,000.00		517,297.72			13-Dec-2005		5.663%		CA - 80.00%		Paid Off - 360		01-Sep-2005
121828478 2			900,000.00		894,283.60			02-Dec-2005		6.263%		CA - 75.00%		Paid Off - 360		01-Sep-2005
121830735 1			345,000.00		345,438.59			29-Nov-2005		6.250%		CA - 79.49%		Paid Off - 360		01-Sep-2005
121836338 1			140,000.00		139,899.18			12-Dec-2005		6.163%		VA - 80.00%		Paid Off - 360		01-Oct-2005
121837212 1			178,000.00		177,871.78			13-Dec-2005		6.013%		MD - 68.46%		Paid Off - 360		01-Oct-2005


Page 23 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution

Prepayment Detail Report - Mortgage Loans Prepaid in Full During Current Distribution
Loan Number			Original							Current		State &		Type Prepayment		First


&		Loan	Principal		Prepayment			Prepayment		Note		LTV at		&		Payment

Loan Group		Status	Balance		Amount			Date		Rate		Origination		Original Term		Date

121879155 1			265,600.00		265,452.86			06-Dec-2005		6.213%		NY - 80.00%		Paid Off - 360		01-Oct-2005

121583911 1			243,750.00		244,040.30			30-Nov-2005		6.263%		CA - 75.00%		Repur/Subs - 360		01-Sep-2005


TOTAL			28,752,098.00		28,768,679.10



Page 24 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Realized Loss Report

COLLATERAL REALIZED LOSSES



											Group 2		Group 1		Total


Current




Number of Loans Liquidated										0		0		0
Collateral Principal Realized Loss/(Gain) Amount										0.00		0.00		0.00
Collateral Interest Realized Loss/(Gain) Amount										0.00		0.00		0.00
Net Liquidation Proceeds										0.00		0.00		0.00

Cumulative




Number of Loans Liquidated										0		0		0
Collateral Realized Loss/(Gain) Amount										0.00		0.00		0.00
Net Liquidation Proceeds										0.00		0.00		0.00










Page 25 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution


DEFAULT SPEEDS



											Group 2		Group 1		Total



MDR										0.00%		0.00%		0.00%
3 Months Avg MDR										0.00%		0.00%		0.00%
12 Months Avg MDR										0.00%		0.00%		0.00%
Avg MDR Since Cut-off										0.00%		0.00%		0.00%


CDR										0.00%		0.00%		0.00%
3 Months Avg CDR										0.00%		0.00%		0.00%
12 Months Avg CDR										0.00%		0.00%		0.00%
Avg CDR Since Cut-off										0.00%		0.00%		0.00%


SDA										0.00%		0.00%		0.00%
3 Months Avg SDA Approximation										0.00%		0.00%		0.00%
12 Months Avg SDA Approximation										0.00%		0.00%		0.00%
Avg SDA Since Cut-off Approximation										0.00%		0.00%		0.00%


Loss Severity Approximation for Current Period										0.00%		0.00%		0.00%
3 Months Avg Loss Severity Approximation										0.00%		0.00%		0.00%
12 Months Avg Loss Severity Approximation										0.00%		0.00%		0.00%
Avg Loss Severity Approximation Since Cut-off										0.00%		0.00%		0.00%












Page 26 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution





COLLATERAL REALIZED LOSS CALCULATION METHODOLOGY
	Monthly Default Rate (MDR): (Beg Principal Balance of Liquidated Loans)/(Total Beg Principal Balance)



	Conditional Default Rate (CDR): 1-((1-MDR)^12)

	SDA Standard Default Assumption: CDR/IF(WAS<61,MIN(30,WAS)0.02,MAX(0.03,MIN(30,WAS)0.02-0.0095*(WAS-60)))

	Average MDR over period between nth month and mth month (AvgMDRn,m): [(1-MDRn)(1-MDRn+1)...*(1-MDRm)]^(1/months in period n,m)
	Average CDR over period between the nth month and mth month (AvgCDRn,m): 1-((1-AvgMDRn,m)^12)

	Average SDA Approximation over period between the nth month and mth month:
	AvgCDRn,m/IF(Avg WASn,m<61,MIN(30,Avg WASn,m)0.02,MAX(0.03,MIN(30,Avg WASn,m)0.02-0.0095*(Avg WASn,m-60)))

	Average WASn,m: (WASn + WASn+1 +...+ WASm )/(number of months in the period n,m)
	Loss Severity Approximation for current period: sum(Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans)

	Average Loss Severity Approximation over period between nth month and mth month: Avg(Loss Severityn,m)

	Note: Default rates are calculated since deal issue date and include realized gains and additional realized losses and gains from prior periods.
	Dates correspond to distribution dates.




Page 27 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Realized Loss Detail Report
Loan Number			Current		State &				Prior		Realized				Cumulative

&		Loan	Note		LTV at		Original		Principal		Loss/(Gain)		Realized		Realized

Loan Group		Status	Rate		Origination		Term		Balance		Revision		Loss/(Gain)		Loss/(Gain)





TOTAL



Page 28 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Triggers and Adj. Cert. Report
TRIGGER EVENTS

										Group 2		Group 1		Total
						Has Optional Termination Date Reached (0=No,1=Yes)								0
						Has Sr. Prepay Stepdown Condition Occurred								0
						Has Sr. Credit Supp. Depletion Date Occured								0



ADJUSTABLE RATE CERTIFICATE INFORMATION

SPACE INTENTIONALLY LEFT BLANK



ADDITIONAL INFORMATION

										Group 2		Group 1		Total
Current Senior Percentage										91.596470%		91.655698%		91.624659%
Next Senior Percentage										91.496152%		91.575653%		91.534031%
Current Subordinate Percentage										8.403530%		8.344302%		8.375341%
Next Subordinate Percentage										8.503848%		8.424347%		8.465969%
Senior Prepayment Percentage										100.000000%		100.000000%		100.000000%
Next Senior Prepayment Percentage										100.000000%		100.000000%		100.000000%
Subordinate Prepayment Percentage										0.000000%		0.000000%		0.000000%
Next Subordinate Prepayment Percentage										0.000000%		0.000000%		0.000000%



Page 29 of 30
IndyMac INDX Mortgage Loan Trust 2005-AR18

Mortgage Pass-Through Certificates

2005-AR18

December 27, 2005 Distribution
Other Related Information
ADDITIONAL INFORMATION

										Group 2		Group 1		Total
Current Scheduled Payments										6,266,771.94		5,843,686.13		12,110,458.08
Current Scheduled Payments 1 Month Prior										6,178,624.24		5,737,674.49		11,916,298.73
Current Scheduled Payments 2 Month Prior										5,778,296.93		5,233,539.61		11,011,836.53
Current Scheduled Payments 3 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 4 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 5 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 6 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 7 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 8 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 9 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 10 Month Prior										0.00		0.00		0.00
Current Scheduled Payments 11 Month Prior										0.00		0.00		0.00

1-A-1 Carryforward Amount Paid
1-A-2 Carryforward Amount Paid
1-A-3A Carryforward Amount Paid
1-A-3B Carryforward Amount Paid
2-A-1A Carryforward Amount Paid
2-A-1B Carryforward Amount Paid
2-A-2A Carryforward Amount Paid
2-A-2B Carryforward Amount Paid
2-A-2C Carryforward Amount Paid
2-A-3A Carryforward Amount Paid
2-A-3B Carryforward Amount Paid
B-1 Carryforward Amount Paid
B-2 Carryforward Amount Paid
B-3 Carryforward Amount Paid
B-4 Carryforward Amount Paid
B-5 Carryforward Amount Paid
B-6 Carryforward Amount Paid
B-7 Carryforward Amount Paid
B-8 Carryforward Amount Paid
B-9 Carryforward Amount Paid
B-10 Carryforward Amount Paid
B-11 Carryforward Amount Paid




Page 30 of 30

INDYMAC INDX MORTGAGE LOAN TRUST 2005-AR18 8-K