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) ~~August~~September 2527, 2004

Structured Asset Securities Corporation
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction
of incorporation)

333-115858
(Commission
File Number)

74-2440850
(IRS Employer
Identification No.)

745 Seventh Avenue, 7th Floor, New York, NY
(Address of principal executive offices)

10019
(Zip Code)

Registrant's telephone number, including area code 212-526-7000

(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 under the Exchange Act (17 CFR 240.14a-12)

[ ] 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))

Section 8 - Other Events

Item 8.01. Other Events.

This current report on Form 8-K relates to the monthly distribution reported to the holders of Structured Asset Securities Corporation Mortgage Pass-Through Certificates Series 2004-13, which was made on ~~August~~September 2527, 2004.

Section 9 - Financial Statements and Exhibits

Item 9.01 Financial Statements and Exhibits.

99.1 Monthly distribution report pursuant to section 5.02 of the Trust Agreement for the distribution on ~~August~~September 2527, 2004.

(Exhibit No. Description)

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.

LASALLE BANK NATIONAL ASSOCIATION, IN ITS CAPACITY AS TRUSTEE UNDER THE TRUST AGREEMENT ON BEHALF OF STRUCTURED ASSET SECURITIES CORPORATION, REGISTRANT

By: /s/ Russell Goldenberg Russell Goldenberg Group Senior Vice President Date: ~~August~~September 30, 2004

STRUCTURED ASSET SECURITIES CORPORATION Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 Reporting Package Table of Contents Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Administrator: Rita Lopez 312.904.0351rita.lopez@abnamro.com Analyst:~~David~~ ~~Ratner~~Luis Clemente 714.259.~~6251~~6268 ~~david~~Luis.~~ratner~~Clemente@abnamro.com Statement Date: 135 S. LaSalle Street, Suite 1625Chicago, IL 60603USA Statements to CertificateholdersBond Interest ReconciliationSubstitution Detail HistoryOther Related Information Cash Reconciliation Summary Shortfall Summary ReportAsset-Backed Facts ~ 15 Month Loan Status Summary Realized Loss DetailHistorical REO Report Page 2-3Page 4Page 5Page 6 Page 7-9 Page 10Page 11-13 Page 14Page 15 Page(s) Information is available for this issue from the following sources Issue Id: Monthly Data ~~FileName~~File Name: SASC0413 ~~SASC0413_200408_3~~SASC0413_200409_3.ZIP Closing Date: First Payment Date: Rated Final Payment: Date: 30-Jun-0426-Jul-04 27-Jul-37 Parties to The Transaction Issuer: Structured Asset Securities Corporation Underwriter: Lehman Brothers Inc. Master Servicer: Aurora Loan Services, Inc. Rating Agency: Standard & Poor's/Moody's Investors Service, Inc./Fitch Ratings 800.246.5761 LaSalle Factor Line LaSalle Web Site Servicer Web Site www.alservices.com www.etrustee.net Page 1 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 6.~~021178~~017880% 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 STRUCTURED ASSET SECURITIES CORPORATION Mortgage Pass-Through Certificates Series 2004-13 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate ~~356~~355 REMIC II Statement Date: ABN AMRO Acct: 721911.2 1000.000000000 0.000000000 0.000000000 1000.000000000 4.583333986 Fixed 0.00 0.00 0.000000000 5.50000000% 0.000000000 86359BVL2 1-A1 5,111,000.00 5,111,000.00 0.00 0.00 5,111,000.00 23,425.42 ~~999~~998.~~167474280~~272613582 02.~~894860697~~832730732 0.000000000 ~~998~~995.~~272613582~~439882851 4.~~579517635~~575416156 Fixed 0.00 0.00 0.000000000 5.50000000% 0.000000000 86359BVM0 1-A2 39,949,000.00 39,~~915~~879,~~741~~992.4364 35113,~~748~~164.7976 0.00 39,~~879~~766,~~992~~827.6488 182,~~947~~783.1530 1000.000000000 0.000000000 0.000000000 1000.000000000 4.583335156 Fixed 0.00 0.00 0.000000000 5.50000000% 0.000000000 86359BVN8 1-A3 1,829,000.00 1,829,000.00 0.00 0.00 1,829,000.00 8,382.92 ~~990~~979.~~804901654~~234057323 1110.~~570844330~~272971663 0.000000000 ~~979~~968.~~234057323~~961085660 4.~~790563946~~731884776 5.~~798676714~~795244346% 0.00 0.00 0.000000000 5.~~80202693~~79867671% 0.000000000 86359BVT5 2-A1 415,572,000.00 ~~411~~406,~~750~~942,~~774~~255.5967 4,~~808~~269,~~518~~159.9238 0.00 ~~406~~402,~~942~~673,~~255~~096.6729 1,~~990~~966,~~824~~438.2482 ~~999~~998.~~050355400~~099694319 0.~~950661081~~963323819 0.000000000 ~~998~~997.~~099694319~~136370500 4.~~804917595~~797831691 5.~~768359688~~765263432% 0.00 0.00 0.000000000 5.~~77138211~~76835969% 0.000000000 86359BVP3 B1 10,861,000.00 10,~~850~~840,~~685~~360.9178 10,~~325~~462.1366 0.00 10,~~840~~829,~~360~~898.7812 52,~~186~~109.2125 ~~999~~998.~~050356354~~099696133 0.~~950660221~~963323204 0.000000000 ~~998~~997.~~099696133~~136372928 4.~~804917127~~797831492 5.~~768359688~~765263432% 0.00 0.00 0.000000000 5.~~77138211~~76835969% 0.000000000 86359BVQ1 B2 3,620,000.00 3,~~616~~613,~~562~~120.2990 3,~~441~~487.3923 0.00 3,~~613~~609,~~120~~633.9067 17,~~393~~368.8015 ~~999~~998.~~050357513~~099694301 0.~~950663212~~963326425 0.000000000 ~~998~~997.~~099694301~~136367876 4.~~804917098~~797834197 5.~~768359688~~765263432% 0.00 0.00 0.000000000 5.~~77138211~~76835969% 0.000000000 86359BVR9 B3 1,930,000.00 1,~~928~~926,~~167~~332.1941 1,~~834~~859.7822 0.00 1,~~926~~924,~~332~~473.4119 9,~~273~~259.4982 ~~999~~998.~~050355240~~099692126 0.~~950663114~~963321492 0.000000000 ~~998~~997.~~099692126~~136370634 4.~~804920071~~797833037 5.~~768359688~~765263432% 0.00 0.00 0.000000000 5.~~77138211~~76835969% 0.000000000 86359BVU2/U85985RQ1 B4 1,689,000.00 1,~~687~~685,~~396~~790.0538 1,~~605~~627.6705 0.00 1,~~685~~684,~~790~~163.3833 8,~~115~~103.5154 ~~999~~998.~~050352210~~099689227 0.~~950662983~~963321823 0.000000000 ~~998~~997.~~099689227~~136367403 4.~~804917127~~797831492 5.~~768359688~~765263432% 0.00 0.00 0.000000000 5.~~77138211~~76835969% 0.000000000 86359BVV0/U85985RR9 B5 1,448,000.00 1,~~446~~445,~~624~~248.9135 1,~~376~~394.5689 0.00 1,~~445~~443,~~248~~853.3546 6,~~957~~947.5226 ~~999~~998.~~050358389~~099701045 0.~~950657344~~963326553 0.000000000 ~~998~~997.~~099701045~~136374492 4.~~804924383~~797827979 5.~~768359688~~765263432% 0.00 0.00 0.000000000 5.~~77138211~~76835969% 0.000000000 86359BVW8/U85985RS7 B6 728,538.00 727,~~846~~153.1556 ~~692~~701.5982 0.00 ~~727~~726,~~153~~451.5674 3,~~500~~495.5740 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 Fixed 0.00 0.00 0.000000000 N/A 0.000000000 86359BVS7 R 100.00 0.00 0.00 0.00 0.00 0.00 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 9ABSR034 R-1 0.00 0.00 0.00 0.00 0.00 0.00 Total P&I Payment 0.00 0.00 482,737,638.00 ~~478~~474,~~863~~000,~~798~~254.5269 76,~~166~~680,~~550~~170.6689 Total ~~474~~469,~~000~~598,~~254~~397.6968 4,~~863~~401,~~543~~857.8301 0.00 2,~~303~~278,~~006~~313.8388 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Page 2 of 15 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 0 Per $ 0 Per $ 0 Per $ 0 Per $ 0 Per $ 0 Per $ 0 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 6.~~021178~~017880% 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 STRUCTURED ASSET SECURITIES CORPORATION Mortgage Pass-Through Certificates Series 2004-13 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate ~~356~~355 Grantor Trust Statement Date: ABN AMRO Acct: 721911.2 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 ~~10,713~~0.0400 0.000000000 N/A 0.000000000 9ABSR032 P 0.00 0.00 0.00 0.00 0.00 ~~10,713~~0.0400 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 9ABSR033 E 0.00 0.00 0.00 0.00 0.00 0.00 Total P&I Payment 0.00 ~~10,713~~0.0400 0.00 0.00 ~~10,713~~0.0400 Total 0.00 0.00 0.00 ~~10,713~~0.0400 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Page 3 of 15 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class STRUCTURED ASSET SECURITIES CORPORATION Class Accrued Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.22Bond ~~Bond~~ Interest Reconciliation Deductions Allocable Deferred & Prior Prepay- Other Additions Interest Credit Support Original Current(4) Accrual Int. Short- falls Due ment Interest Interest (2) Payment Amount PPIS Interest Certificate Accretion Interest Loss/Exp Interest Penalties Proceeds (1) Interest Shortfalls Certificate Rate ~~Pass~~PassThru ~~Thru~~ Method Days Outstanding Remaining Statement Date: Distributable Current Period (Shortfall)/ Recovery Int Accrual on Prior Shortfall (3) 0.00 0.00 0.00 0.00 0.00 1-A1 30 23,425.42 23,425.42 23,425.42 0.00 4.20% 4.2731% 30/360 5.500000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1-A2 30 182,~~947~~783.1530 182,~~947~~783.1530 182,~~947~~783.1530 0.00 4.20% 4.2731% 30/360 5.500000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1-A3 30 8,382.92 8,382.92 8,382.92 0.00 4.20% 4.2731% 30/360 5.500000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2-A1 30 1,~~990~~966,~~824~~438.2482 1,~~990~~966,~~824~~438.2482 1,~~990~~966,~~824~~438.2482 0.00 4.20% 4.2731% 30/360 5.~~802026934~~798676714% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B1 30 52,~~186~~109.2125 52,~~186~~109.2125 52,~~186~~109.2125 0.00 1.95% 12.9800% 30/360 5.~~771382108~~768359688% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B2 30 17,~~393~~368.8015 17,~~393~~368.8015 17,~~393~~368.8015 0.00 1.20% 1.2223% 30/360 5.~~771382108~~768359688% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B3 30 9,~~273~~259.4982 9,~~273~~259.4982 9,~~273~~259.4982 0.00 0.80% 0.8182% 30/360 5.~~771382108~~768359688% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B4 30 8,~~115~~103.5154 8,~~115~~103.5154 8,~~115~~103.5154 0.00 0.45% 0.46% 30/360 5.~~771382108~~768359688% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B5 30 6,~~957~~947.5226 6,~~957~~947.5226 6,~~957~~947.5226 0.00 0.15% 0.15% 30/360 5.~~771382108~~768359688% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B6 30 3,~~500~~495.5740 3,~~500~~495.5740 3,~~500~~495.5740 0.00 0.00% 0.00% 30/360 5.~~771382108~~768359688% 0.00 0.00 0.00 0.00 ~~10,713~~0.0400 0.00 0.00 0.00 P 30 0.00 ~~10,713~~0.0400 ~~10,713~~0.0400 0.00 NA NA 30/360 0.000000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 E 30 0.00 0.00 0.00 0.00 NA NA 30/360 0.000000000% 0.00 0.00 0.00 0.00 0.00 0.00 ~~10,713~~0.0400 0.00 2,~~303~~278,~~006~~313.8388 2,~~313~~278,~~719~~313.8788 2,~~313~~278,~~719~~313.8788 0.00 0.00 0.00 0.00 (2) Accrued - Deductions + Additions Interest (3) Includes interest accrued on outstanding Interest Shortfalls and/or Loss Allocations. Where applicable. 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Page 4 of 15 (1) Other Interest Proceeds are additional interest amounts specifically allocated to the bond(s) and used in determining the bonds Distributable Interest. (4) Determined as follows: (A) the ending balance of all the classes less (B) the sum of (i) the ending balance of the class and (ii) the ending balance of all classes which are not subordinate to the class divided by (A). STRUCTURED ASSET SECURITIES CORPORATION Substitution Detail History ABN AMRO Acct: 721911.2 Series 2004-13 Mortgage Pass-Through Certificates 3031-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 2625-~~Jul~~Aug-04 2527-~~Aug~~Sep-04 2527-~~Aug~~Sep-04 Record Date: Next Payment: Prior Payment: Payment Date: Statement Date: Property ID Deleted Loan Qualified Substitute Scheduled Prin Bal 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Page 5 of 15 Original Property Per Section 7.01(a)(i) of the Property Management and Lease Servicing Agreement, aggregate Appraised Value of the Qualified Substitute Mortgaged Properties acquired by ~~theIssuer~~the Issuer since the Closing Date in connection with the substitution or exchange pursuant to Section 7.01 is not to exceed 25% of the aggregate Initial Appraised Value of ~~theMortgaged~~the Mortgaged Properties. (A) STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 ~~Statement Date:~~ Other Related Information Statement Date: Special Hazard Coverage Beginning Balance Current Reduction Ending Balance Beginning Balance Current Reduction Beginning Balance Current Reduction Ending Balance Fraud Loss Coverage Bankruptcy Loss Coverage Ending Balance Number of Payoffs:Aggregate Payoff Amounts: Number of Curtailments:Aggregate Curtailment Amounts: Number of Loans in Foreclosure:Book Value of Loans in Foreclosure: Prior Realized Losses Allocated to the Certificates: Current Realized Losses Allocated to the Certificates:Cumulative Realized Losses Allocated to the Certificates since Cutoff: Group I Group II Total 40 3,~~827~~790,~~376~~640.0026 421 3,~~827~~790,~~376~~640.26 432 154,078.53 0 0.00 0.00 90.00 0.000.00 21 0.00 0.00 Beginning Principle Balance: Ending Principle Balance: 474,~~654~~000,~~753~~255.0039 9469,~~654~~598,~~753~~398.37 0.00 0.00 ~~100,000~~0.00 ~~100~~87,~~000~~155.88 66,922.65 22 410 0 0 0.00 0.00 250.00 40.00 0.00 0.00 48,~~061~~874,~~782~~241.7912 ~~459~~48,759,935.21 425,126,014.27 420,838,463.16 85 Ending Loan Count: Sched Prin: 2,286 429,988.20 27,150.03 Special Hazard Loss:Fraud Loss:Bankruptcy Loss: 0.000.000.00 0.000.000.00 2,371 0.000.00 457,138.23 0.00 ~~346~~4,~~235~~740,002.2855 4,740,002.55 9,654,753.00 9,654,753.00 100,000.00 100,000.00 Page 6 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 Statement Date: Cash Reconciliation Summary Current Scheduled Interest Interest Summary Less Deferred Interest Plus Gross Advance Interest Less PPIS Reducing Scheduled Int ~~740~~680,~~011~~941.0289 0.~~000.~~00 ) (2,297.46 Less ASER Interest Adv Reduction 0.00 Less Other Adjustment 0.00 Total 2,~~333~~304,~~657~~328.2822 Unscheduled Interest:Prepayment Penalties ~~10,713~~0.0400 Yield Maintenance Penalties 0.00 Other Interest Proceeds 0.00 Total ~~10,713~~0.0400 Less Fees & Expenses Paid By/To Servicer Less Fee Paid To Servicer Less Fee Strips Paid by Servicer Special Servicing Fees Interest Due Serv on ~~Advances~~AdvancesRecoup ~~Recoup~~ of Prior ~~Advances Misc~~AdvancesMisc. Fees & Expenses Total Unscheduled Fees & ~~ExpensesTotal~~Expenses Total Interest Due Trust Less Fees & Expenses Paid By/To TrustTrustee FeeFee StripsMisc. FeesInterest Reserve ~~Withholding~~WithholdingPlus ~~Plus~~ Interest Reserve DepositTotal Total Interest Due Certs Principal Summary Scheduled Principal:Current Scheduled PrincipalAdvanced Scheduled PrincipalScheduled PrincipalUnscheduled Principal:CurtailmentsPrepayments in FullLiquidation ProceedsRepurchase ProceedsOther Principal ProceedsTotal Unscheduled Principal Remittance Principal Remittance P&I Due Trust Remittance P&I Due Certs Pool Balance Summary Beginning PoolScheduled PrincipalUnscheduled PrincipalDeferred InterestLiquidationsRepurchases Ending Pool Balance Count Principal Interest Prior ~~OutstandingPlus~~Outstanding Plus Current ~~PeriodLess~~Period Less Recovered Ending Outstanding Servicing Fee Summary Current Servicing FeesPlus Fees Advanced for PPISLess Reduction for PPISPlus Delinquent Servicing Fees Total Servicing Fees PPIS Summary Gross PPISReduced by PPIEReduced by Shortfalls in FeesReduced by Other ~~Amounts~~AmountsPPIS ~~PPIS~~ Reducing ~~ScheduledInterest~~Scheduled ~~PPIS~~InterestPPIS Reducing Servicing ~~FeePPIS~~Fee PPIS Due Certificate 0.00 0.00 0.000.00 0.00 0.00 2,~~313~~278,~~719~~313.8687 0.000.000.000.00 0.00 ~~139~~131,~~484~~230.~~06316~~24325,~~041~~907.~~70455~~99457,~~525~~138.7623 ~~346~~154,~~235~~078.2853 43,~~061~~790,~~782~~640.7926 0.000.000.00 43,~~408~~944,~~018~~718.~~074~~794,~~863~~401,~~543~~857.8302 76,~~177~~680,~~263~~170.6989 76,~~177~~680,~~263~~170.6989 ~~478~~474,~~863~~000,~~799~~255.2239 2,~~417~~392 ~~455~~457,~~525~~138.7623 43,~~408~~944,~~018~~718.0779 2521 0.000.00 0 0.00 0 ~~474~~469,~~000~~598,~~255~~398.3937 2,~~392~~371 ~~312~~319,~~834~~293.9711 1,~~591~~614,~~684~~314.8978 ~~316~~325,~~041~~907.7099 1,~~593~~625,~~646~~683.2679 ~~319~~329,~~293~~580.1128 1,~~614~~643,~~314~~308.7896 3028,~~650~~217.4671 0.~~000.~~00 69) (2,~~112~~203.8336 9970,~~763~~438.2925 096,452.~~000~~60 2,297.~~000~~46 0.~~000~~00 ) (94.~~000~~10 0.~~000.~~00 2,203.362,203.36 0.00 Advance Summary (Advance Made by Servicer) ) (3026,~~650~~014.4635 2,~~313~~278,~~719~~313.8687 Interest Not Advanced ( Current Period ) 0.00 1,~~593~~625,~~646~~683.2679 Workout FeesLiquidation Fees 0.000.00 Less Non Recovered ) (1,~~571~~596,~~016~~689.3761 ) (~~309~~315,~~583~~620.5682 0.00 0.00 0.00 Page 7 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 Statement Date: Cash Reconciliation Summary Pool 1 Current Scheduled Interest Interest Summary Less Deferred Interest Plus Gross Advance Interest Less PPIS Reducing Scheduled Int 4745,~~377~~955.7871 0.000.00 Less ASER Interest Adv Reduction 0.00 Less Other Adjustment 0.00 Total 226,~~235~~005.8901 Unscheduled Interest:Prepayment Penalties 0.00 Yield Maintenance Penalties 0.00 Other Interest Proceeds 0.00 Total 0.00 Less Fees & Expenses Paid By/To Servicer Less Fee Paid To Servicer Less Fee Strips Paid by Servicer Special Servicing Fees Interest Due Serv on ~~Advances~~AdvancesRecoup ~~Recoup~~ of Prior ~~Advances Misc~~AdvancesMisc. Fees & Expenses Total Unscheduled Fees & ~~ExpensesTotal~~Expenses Total Interest Due Trust Less Fees & Expenses Paid By/To TrustTrustee FeeFee StripsMisc. FeesInterest Reserve ~~Withholding~~WithholdingPlus ~~Plus~~ Interest Reserve DepositTotal Total Interest Due Certs Principal Summary Scheduled Principal:Current Scheduled PrincipalAdvanced Scheduled PrincipalScheduled PrincipalUnscheduled Principal:CurtailmentsPrepayments in FullLiquidation ProceedsRepurchase ProceedsOther Principal ProceedsTotal Unscheduled Principal Remittance Principal Remittance P&I Due Trust Remittance P&I Due Certs Pool Balance Summary Beginning PoolScheduled PrincipalUnscheduled PrincipalDeferred InterestLiquidationsRepurchases Ending Pool Balance Count Principal Interest Prior ~~OutstandingPlus~~Outstanding Plus Current ~~PeriodLess~~Period Less Recovered Ending Outstanding Servicing Fee Summary Current Servicing FeesPlus Fees Advanced for PPISLess Reduction for PPISPlus Delinquent Servicing Fees Total Servicing Fees PPIS Summary Gross PPISReduced by PPIEReduced by Shortfalls in FeesReduced by Other ~~Amounts~~AmountsPPIS ~~PPIS~~ Reducing ~~ScheduledInterest~~Scheduled ~~PPIS~~InterestPPIS Reducing Servicing ~~FeePPIS~~Fee PPIS Due Certificate 0.00 0.00 0.000.00 0.00 0.00 224,~~175~~006.9994 0.000.000.000.00 0.00 5,~~332~~402.0803 21,~~656~~748.~~4926~~0027,~~988~~150.5703 987,~~894~~155.3688 0.000.000.000.00 987,~~894~~155.3688 36114,~~882~~305.9391 ~~261~~338,~~058~~312.9285 ~~261~~338,~~058~~312.9285 48,~~911~~874,~~124~~241.0512 85 2627,~~988~~150.~~57 9~~0387,~~894~~155.3688 0 0.000.00 0 0.00 0 48,~~874~~759,~~241~~935.1221 85 21,~~010~~656.8349 ~~172~~183,~~085~~418.3853 21,~~656~~748.4900 ~~178~~180,~~858~~049.1130 21,~~656~~748.4900 ~~183~~180,~~418~~049.5330 21,~~059~~998.9007 0.000.00 8,~~129~~184.9106 10,~~189~~182.8213 0.000.000.000.000.000.00 0.00 Advance Summary (Advance Made by Servicer) ) (21,~~059~~998.9007 224,~~175~~006.9994 Interest Not Advanced ( Current Period ) 0.00 ~~178~~180,~~858~~049.1130 Workout FeesLiquidation Fees 0.000.00 Less Non Recovered ) (~~167~~183,~~524~~418.9753 ) (21,~~010~~656.8349 0.00 0.00 0.00 Page 8 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 Statement Date: Cash Reconciliation Summary Pool 2 Current Scheduled Interest Interest Summary Less Deferred Interest Plus Gross Advance Interest Less PPIS Reducing Scheduled Int ~~692~~634,~~633~~986.2417 0.~~000.~~00 ) (2,297.46 Less ASER Interest Adv Reduction 0.00 Less Other Adjustment 0.00 Total 2,~~107~~078,~~421~~323.3920 Unscheduled Interest:Prepayment Penalties ~~10,713~~0.0400 Yield Maintenance Penalties 0.00 Other Interest Proceeds 0.00 Total ~~10,713~~0.0400 Less Fees & Expenses Paid By/To Servicer Less Fee Paid To Servicer Less Fee Strips Paid by Servicer Special Servicing Fees Interest Due Serv on ~~Advances~~AdvancesRecoup ~~Recoup~~ of Prior ~~Advances Misc~~AdvancesMisc. Fees & Expenses Total Unscheduled Fees & ~~ExpensesTotal~~Expenses Total Interest Due Trust Less Fees & Expenses Paid By/To TrustTrustee FeeFee StripsMisc. FeesInterest Reserve ~~Withholding~~WithholdingPlus ~~Plus~~ Interest Reserve DepositTotal Total Interest Due Certs Principal Summary Scheduled Principal:Current Scheduled PrincipalAdvanced Scheduled PrincipalScheduled PrincipalUnscheduled Principal:CurtailmentsPrepayments in FullLiquidation ProceedsRepurchase ProceedsOther Principal ProceedsTotal Unscheduled Principal Remittance Principal Remittance P&I Due Trust Remittance P&I Due Certs Pool Balance Summary Beginning PoolScheduled PrincipalUnscheduled PrincipalDeferred InterestLiquidationsRepurchases Ending Pool Balance Count Principal Interest Prior ~~OutstandingPlus~~Outstanding Plus Current ~~PeriodLess~~Period Less Recovered Ending Outstanding Servicing Fee Summary Current Servicing FeesPlus Fees Advanced for PPISLess Reduction for PPISPlus Delinquent Servicing Fees Total Servicing Fees PPIS Summary Gross PPISReduced by PPIEReduced by Shortfalls in FeesReduced by Other ~~Amounts~~AmountsPPIS ~~PPIS~~ Reducing ~~ScheduledInterest~~Scheduled ~~PPIS~~InterestPPIS Reducing Servicing ~~FeePPIS~~Fee PPIS Due Certificate 0.00 0.00 0.000.00 0.00 0.00 2,~~089~~054,~~543~~306.8793 0.000.000.000.00 0.00 ~~134~~125,~~151~~828.~~98294~~21304,~~385~~159.~~21428~~99429,~~537~~988.1920 ~~336~~66,~~340~~922.9265 43,~~061~~790,~~782~~640.7926 0.000.000.00 43,~~398~~857,~~123~~562.~~714~~914,~~826~~287,~~660~~551.9011 6,~~916~~341,~~204~~858.7704 6,~~916~~341,~~204~~858.7704 ~~429~~425,~~952~~126,~~675~~014.1727 2,~~332~~307 ~~428~~429,~~537~~988.1920 43,~~398~~857,~~123~~562.7191 2521 0.000.00 0 0.00 0 ~~425~~420,~~126~~838,~~014~~463.2716 2,~~307~~286 ~~291~~297,~~824~~636.1462 1,~~419~~430,~~599~~896.5125 ~~294~~304,~~385~~159.2199 1,~~414~~445,~~788~~634.1549 ~~297~~307,~~636~~832.6228 1,~~430~~463,~~896~~259.2566 2826,~~590~~219.5663 0.~~000.~~00 60) (2,~~982~~203.9236 8962,~~573~~254.4719 086,270.~~000~~46 2,297.~~000~~46 0.~~000~~00 ) (94.~~000~~10 0.~~000.~~00 2,203.362,203.36 0.00 Advance Summary (Advance Made by Servicer) ) (2824,~~590~~016.5627 2,~~089~~054,~~543~~306.8793 Interest Not Advanced ( Current Period ) 0.00 1,~~414~~445,~~788~~634.1549 Workout FeesLiquidation Fees 0.000.00 Less Non Recovered ) (1,~~403~~413,~~491~~271.4009 ) (~~288~~293,~~572~~964.7333 0.00 0.00 0.00 Page 9 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 Interest Adjustments Summary Statement Date: 0.00 0.00 0.00 0.00 Special Servicing Fees Workout Fees Liquidation Fees Legal Fees 0.00 0.00 Misc. Fees & Expenses Paid by/to Servicer Interest Paid to Servicer on Outstanding Advances 0.00 0.00 ASER Interest Advance Reduction Interest Not Advanced (Current Period) Recoup of Prior Advances by Servicer 0.00 0.00 Servicing Fees Paid Servicer on Loans Not Advanced Misc. Fees & Expenses Paid by Trust 0.00 0.00 0.00 Shortfall Due to Rate Modification Total Shortfall Allocated to the Bonds Total Interest Adjustment to the Bonds 0.00 Shortfall Allocated to the Bonds: Excess Allocated to the Bonds: Other Interest Proceeds Due the Bonds Yield Maintenance Penalties Due the Bonds Prepayment Penalties Due the Bonds Recovered ASER Interest Due the Bonds Recovered Interest Due the Bonds Less Total Shortfall Allocated to the Bonds Total Excess Allocated to the Bonds ~~10,713~~0.0400 ~~10,713~~0.0400 Total Excess Allocated to the Bonds ~~10,713~~0.0400 0.00 Aggregate Interest Adjustment Allocated to the Bonds 0.00 ~~10,713~~0.0400 0.00 0.00 Prepayment Interest Excess Due the Bonds 0.00 ARD Excess Interest 0.00 ~~Other Interest Loss~~ 0.00 0.00 Net Prepayment Int. Shortfalls Allocated to the Bonds Other Interest Loss Page 10 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Distribution Date Delinq 1 Month Delinq 2 Months Delinq 3+ Months Foreclosure REO Modifications Specially Serviced Bankruptcy # Balance # Balance # Balance # Balance # Balance # Balance # Balance # Balance Delinquency Aging Categories Special Event Categories (1) Statement Date: ABN AMRO Acct: 721911.2 0.93% 0.80% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.08% 0.07% 0.00% 0.00% 27-Sep-04 22 3,759,066 0 0 0 0 0 0 0 0 0 0 2 310,989 0.96% 0.94% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 25-Aug-04 23 4,452,876 0 0 0 0 0 0 0 0 0 0 0 0 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 26-Jul-04 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category Page 11 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Distribution Date Delinq 1 Month Delinq 2 Months Delinq 3+ Months Foreclosure REO Modifications Specially Serviced Bankruptcy # Balance # Balance # Balance # Balance # Balance # Balance # Balance # Balance Delinquency Aging Categories Special Event Categories (1) Statement Date: Pool 1 ABN AMRO Acct: 721911.2 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 27-Sep-04 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1.18% 2.04% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 25-Aug-04 1 995,000 0 0 0 0 0 0 0 0 0 0 0 0 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 26-Jul-04 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category Page 12 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Distribution Date Delinq 1 Month Delinq 2 Months Delinq 3+ Months Foreclosure REO Modifications Specially Serviced Bankruptcy # Balance # Balance # Balance # Balance # Balance # Balance # Balance # Balance Delinquency Aging Categories Special Event Categories (1) Statement Date: Pool 2 ABN AMRO Acct: 721911.2 0.96% 0.89% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.09% 0.07% 0.00% 0.00% 27-Sep-04 22 3,759,066 0 0 0 0 0 0 0 0 0 0 2 310,989 0.95% 0.81% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 25-Aug-04 22 3,457,876 0 0 0 0 0 0 0 0 0 0 0 0 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 26-Jul-04 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category Page 13 of 15 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 ABN AMRO Acct: 721911.2 Realized Loss Detail Period Disclosure Control # Appraisal Date Appraisal Value BeginningScheduled Balance Gross Proceeds Gross Proceeds as a % of Sched. Balance Aggregate ~~Liquidation~~LiquidationExpenses ~~Expenses~~ * Net Liquidation Proceeds Net Proceeds as a % of Sched. Balance Realized Loss Statement Date: Current TotalCumulative 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Page 14 of 15 * Aggregate liquidation expenses also include outstanding P&I advances and unpaid servicing fees, unpaid trustee fees, etc.. STRUCTURED ASSET SECURITIES CORPORATION Payment Date:Prior Payment:Next Payment:Record Date: 2527-~~Aug~~Sep-~~0425~~0427-~~Aug~~Sep-04 2625-~~Jul~~Aug-04 2725-~~Sep~~Oct-04 3031-~~Jul~~Aug-04 Mortgage Pass-Through Certificates Series 2004-13 Historical Collateral Level REO Report Property Type Statement Date: State Actual Balance Scheduled Balance Recent Appraisal Value Appraisal Reduction Amount Date Liquidated Liquidation Proceeds Liquidation Expenses Realized Loss Disclosure Control # REO Date City Appraisal Date ABN AMRO Acct: 721911.2 2023-~~Aug~~Sep-2004 - 1611:2514 (R021-R036, R115) (c) 2004 LaSalle Bank N.A. Page 15 of 15

Filing Compare · Structured Asset Securities CORP Mortgage Pass-Through Certificates, Series 2004-13