WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005

Class	Cusip	Orig Prin Bal	Begin Prin Bal	Int Rate Accrued	Int Rate Paid	Int Dist	Prin Dist	Int Shortfall	PPIS	Uncomp Int Shortfall	Prin Loss	Deferred Interest	Int Reimbursed	Unsched Int	Prin Reimbursed	Subsequent Recoveries	Total Dist	Ending Class Bal
A1	92922FQ27	$417,177,000.00	$393,867,234.86	4.9434307907%	4.9434307907%	$1,622,546.18	$14,403,645.32	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$16,026,191.50	$379,463,589.54
A2	92922FQ35	$105,072,000.00	$105,072,000.00	4.5380000000%	4.5380000000%	$397,347.28	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$397,347.28	$105,072,000.00
A3	92922FQ43	$142,822,000.00	$142,822,000.00	4.4250000000%	4.4250000000%	$526,656.13	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$526,656.13	$142,822,000.00
A4	92922FQ50	$150,000,000.00	$144,742,719.54	4.9434307907%	4.9434307907%	$596,271.35	$3,248,595.71	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$3,844,867.06	$141,494,123.83
X	92922FQ68	$247,894,000.00	$247,894,000.00	0.4705347706%	0.4705347706%	$97,202.29	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$97,202.29	$247,894,000.00
B1	92922FQ76	$18,738,000.00	$18,736,632.44	4.9434307907%	4.9434307907%	$77,186.04	$1,516.73	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$78,702.77	$18,735,115.71
B2	92922FQ84	$6,388,000.00	$6,387,533.78	4.9434307907%	4.9434307907%	$26,313.61	$517.07	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$26,830.68	$6,387,016.71
B3	92922FQ92	$3,833,000.00	$3,832,720.26	4.9434307907%	4.9434307907%	$15,788.99	$310.26	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$16,099.25	$3,832,410.00
B4	92922FR34	$3,407,000.00	$3,406,751.35	4.9434307907%	4.9434307907%	$14,034.20	$275.78	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$14,309.98	$3,406,475.57
B5	92922FR42	$2,555,000.00	$2,554,813.53	4.9434307907%	4.9434307907%	$10,524.62	$206.81	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$10,731.43	$2,554,606.72
B6	92922FR59	$1,702,272.45	$1,702,148.21	4.9434307907%	4.9434307907%	$7,012.04	$137.79	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$7,149.83	$1,702,010.42
R	92922FR26	$100.00	$0.00	0.0000000000%	0.0000000000%	$0.57	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.57	$0.00
TFEE	XXXXXXXXX	$0.00	$0.00	0.0000000000%	0.0000000000%	$685.94	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$685.94	$0.00
R_SYN	XXXXXXXXX	$0.00	$0.00	0.0000000000%	0.0000000000%	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
Total		$851,694,372.45	$823,124,553.97			$3,390,883.29	$17,655,205.48	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$21,046,088.77	$805,469,348.49

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005

Class	Orig Face	Beg Bal	Prin Loss	Prin Reimbursed	Subsequent Recoveries	Deferred Interest	Total Prin	End Cert Pct	End Cert Bal
A1	$417,177,000.00	$393,867,234.86	$0.00	$0.00	$0.00	$0.00	$14,403,645.32	0.9095985386	$379,463,589.54
A2	$105,072,000.00	$105,072,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	1.0000000000	$105,072,000.00
A3	$142,822,000.00	$142,822,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	1.0000000000	$142,822,000.00
A4	$150,000,000.00	$144,742,719.54	$0.00	$0.00	$0.00	$0.00	$3,248,595.71	0.9432941589	$141,494,123.83
X	$247,894,000.00	$247,894,000.00	$0.00	$0.00	$0.00	$0.00	$0.00	1.0000000000	$247,894,000.00
B1	$18,738,000.00	$18,736,632.44	$0.00	$0.00	$0.00	$0.00	$1,516.73	0.9998460727	$18,735,115.71
B2	$6,388,000.00	$6,387,533.78	$0.00	$0.00	$0.00	$0.00	$517.07	0.9998460723	$6,387,016.71
B3	$3,833,000.00	$3,832,720.26	$0.00	$0.00	$0.00	$0.00	$310.26	0.9998460736	$3,832,410.00
B4	$3,407,000.00	$3,406,751.35	$0.00	$0.00	$0.00	$0.00	$275.78	0.9998460728	$3,406,475.57
B5	$2,555,000.00	$2,554,813.53	$0.00	$0.00	$0.00	$0.00	$206.81	0.9998460744	$2,554,606.72
B6	$1,702,272.45	$1,702,148.21	$0.00	$0.00	$0.00	$0.00	$137.79	0.9998460705	$1,702,010.42
R	$100.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	0.0000000000	$0.00
TFEE	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	0.0000000000	$0.00
R_SYN	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	0.0000000000	$0.00
Total	$851,694,372.45	$823,124,553.97	$0.00	$0.00	$0.00	$0.00	$17,655,205.48	0.9457258079	$805,469,348.49

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005
PER $1000 DENOMINATION
Class	Orig Face	Beg Bal	Prin Loss	Prin Reimbursed	Subsequent Recoveries	Deferred Interest	Total Prin	End Cert Pct	End Cert Bal
A1	$417,177,000.00	944.12499936	0.00000000	0.00000000	0.00000000	0.00000000	34.52646076	0.9095985386	909.59853861
A2	$105,072,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
A3	$142,822,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
A4	$150,000,000.00	964.95146360	0.00000000	0.00000000	0.00000000	0.00000000	21.65730473	0.9432941589	943.29415887
X	$247,894,000.00	1,000.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	1.0000000000	1,000.00000000
B1	$18,738,000.00	999.92701676	0.00000000	0.00000000	0.00000000	0.00000000	0.08094407	0.9998460727	999.84607269
B2	$6,388,000.00	999.92701628	0.00000000	0.00000000	0.00000000	0.00000000	0.08094396	0.9998460723	999.84607232
B3	$3,833,000.00	999.92701800	0.00000000	0.00000000	0.00000000	0.00000000	0.08094443	0.9998460736	999.84607357
B4	$3,407,000.00	999.92701790	0.00000000	0.00000000	0.00000000	0.00000000	0.08094511	0.9998460728	999.84607279
B5	$2,555,000.00	999.92701761	0.00000000	0.00000000	0.00000000	0.00000000	0.08094325	0.9998460744	999.84607436
B6	$1,702,272.45	999.92701521	0.00000000	0.00000000	0.00000000	0.00000000	0.08094474	0.9998460705	999.84607047
R	$100.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000
TFEE	$0.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000
R_SYN	$0.00	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.0000000000	0.00000000

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005

Class	Orig Face	Int Rate Accrued	Int Rate Paid	Beg Cert Prin/Not Bal	Current Int Accrued	Int Shortfall	PPIS	Uncompensated Int Shortfall	Unscheduled Int	Int Reimbursed	Total Int Dist
A1	$417,177,000.00	4.9434307907%	4.9434307907%	$393,867,234.86	$1,622,546.18	$0.00	$0.00	$0.00	$0.00	$0.00	$1,622,546.18
A2	$105,072,000.00	4.5380000000%	4.5380000000%	$105,072,000.00	$397,347.28	$0.00	$0.00	$0.00	$0.00	$0.00	$397,347.28
A3	$142,822,000.00	4.4250000000%	4.4250000000%	$142,822,000.00	$526,656.13	$0.00	$0.00	$0.00	$0.00	$0.00	$526,656.13
A4	$150,000,000.00	4.9434307907%	4.9434307907%	$144,742,719.54	$596,271.35	$0.00	$0.00	$0.00	$0.00	$0.00	$596,271.35
X	$247,894,000.00	0.4705347706%	0.4705347706%	$247,894,000.00	$97,202.29	$0.00	$0.00	$0.00	$0.00	$0.00	$97,202.29
B1	$18,738,000.00	4.9434307907%	4.9434307907%	$18,736,632.44	$77,186.04	$0.00	$0.00	$0.00	$0.00	$0.00	$77,186.04
B2	$6,388,000.00	4.9434307907%	4.9434307907%	$6,387,533.78	$26,313.61	$0.00	$0.00	$0.00	$0.00	$0.00	$26,313.61
B3	$3,833,000.00	4.9434307907%	4.9434307907%	$3,832,720.26	$15,788.99	$0.00	$0.00	$0.00	$0.00	$0.00	$15,788.99
B4	$3,407,000.00	4.9434307907%	4.9434307907%	$3,406,751.35	$14,034.20	$0.00	$0.00	$0.00	$0.00	$0.00	$14,034.20
B5	$2,555,000.00	4.9434307907%	4.9434307907%	$2,554,813.53	$10,524.62	$0.00	$0.00	$0.00	$0.00	$0.00	$10,524.62
B6	$1,702,272.45	4.9434307907%	4.9434307907%	$1,702,148.21	$7,012.04	$0.00	$0.00	$0.00	$0.00	$0.00	$7,012.04
R	$100.00	0.0000000000%	0.0000000000%	$0.00	$0.57	$0.00	$0.00	$0.00	$0.00	$0.00	$0.57
TFEE	$0.00	0.0000000000%	0.0000000000%	$0.00	$685.94	$0.00	$0.00	$0.00	$0.00	$0.00	$685.94
R_SYN	$0.00	0.0000000000%	0.0000000000%	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00	$0.00
Total	$851,694,372.45			$823,124,553.97	$3,390,883.29	$0.00	$0.00	$0.00	$0.00	$0.00	$3,390,883.29

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005
PER $1000 DENOMINATION
Class	Orig Face	Int Rate Accrued	Int Rate Paid	Beg Cert Prin/Not Bal	Curent Int Accrued	Int Shortfall	PPIS	Uncompensated Int Shortfall	Unscheduled Int	Int Reimbursed	Total Int Dist
A1	$417,177,000.00	4.9434307907%	4.9434307907%	944.12499936	3.88934716	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	3.88934716
A2	$105,072,000.00	4.5380000000%	4.5380000000%	1,000.00000000	3.78166667	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	3.78166667
A3	$142,822,000.00	4.4250000000%	4.4250000000%	1,000.00000000	3.68750004	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	3.68750004
A4	$150,000,000.00	4.9434307907%	4.9434307907%	964.95146360	3.97514233	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	3.97514233
X	$247,894,000.00	0.4705347706%	0.4705347706%	1,000.00000000	0.39211231	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.39211231
B1	$18,738,000.00	4.9434307907%	4.9434307907%	999.92701676	4.11922510	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.11922510
B2	$6,388,000.00	4.9434307907%	4.9434307907%	999.92701628	4.11922511	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.11922511
B3	$3,833,000.00	4.9434307907%	4.9434307907%	999.92701800	4.11922515	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.11922515
B4	$3,407,000.00	4.9434307907%	4.9434307907%	999.92701790	4.11922512	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.11922512
B5	$2,555,000.00	4.9434307907%	4.9434307907%	999.92701761	4.11922505	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.11922505
B6	$1,702,272.45	4.9434307907%	4.9434307907%	999.92701521	4.11922310	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	4.11922310
R	$100.00	0.0000000000%	0.0000000000%	0.00000000	5.70000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	5.70000000
TFEE	$0.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000
R_SYN	$0.00	0.0000000000%	0.0000000000%	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000	0.00000000

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
MASTER SERVICING
MORTGAGE PASS-THROUGH CERTIFICATES
08/2005 DISTRIBUTION REPORT
SERIES: WAMU 05AR7
WEIGHTED AVERAGE PC RATE: 4.94343%
WEIGHTED AVERAGE MATURITY: 357.12752
WEIGHTED AVERAGE LOAN AGE: 2.38769
POOL NUMBER: 2750
ISSUE DATE: 06/23/2005
CERTIFICATE BALANCE AT ISSUE: $851,694,372.45
	TOTAL NUMBER OF MORTAGES	CERTIFICATE ACCOUNT ACTIVITY (@ PCRATE)	CERTIFICATE BALANCE OUTSTANDING
BALANCES FROM LAST FISCAL MONTH-END:	1309		$823,124,553.97
PRINCIPAL POOL COLLECTION(S):
Scheduled Principal Collection Due Current Month		$66,632.10
Unscheduled Principal Collection/Reversals		$3,671,762.17
Liquidations-in-full	20	$13,916,811.21
Subsequent Recoveries		$0.00
Net principal Distributed		$17,655,205.48	-$17,655,205.48

CAPITAL LOSS (PRINCIPAL WRITTEN OFF):			$0.00

BALANCE CURRENT FISCAL MONTH-END:	1289		$805,469,348.49

SCHEDULED INTEREST AT MORTGAGE RATE:		$3,682,406.62

UNSCHEDULED INTEREST AT MORTGAGE RATE:
Unscheduled Interest Collection/Reversals		$0.00
Interest Uncollected on Liquidation		$0.00
Interest Uncollected on Non-Earning Assets		$0.00
Interest Uncollected on Prepayment		$0.00
Uncompensated Uncollected Interest		$0.00
Net Unscheduled Interest Distributed		$0.00

OTHER:
Loan Conversion Fees		$0.00
Expense Reimbursements		$0.00
Gain on Liquidations		$0.00
Hazard Insurance Premium Refunds		$0.00
Recoveries Carried Forward		$0.00
Net Other Distributions		$0.00

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
MASTER SERVICING
MORTGAGE PASS-THROUGH CERTIFICATES
08/2005 DISTRIBUTION REPORT
	TOTAL NUMBER OF MORTAGES	CERTIFICATE ACCOUNT ACTIVITY (@ PCRATE)	CERTIFICATE BALANCE OUTSTANDING
SCHEDULED SERVICING FEE EXPENSES:		$291,523.33

UNSCHEDULED SERVICING FEES:
Unscheduled Service Fee Collections/Reversals		$0.00
Servicing Fees Uncollected on Liquidation		$0.00
Servicing Fees Uncollected/Non-Earning Assets		$0.00
Net Unscheduled Service Fees Distributed		$0.00

MISCELLANEOUS EXPENSES:		$0.00

NET FUNDS DISTRIBUTED:		$21,046,088.77

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
MASTER SERVICING
MORTGAGE PASS-THROUGH CERTIFICATES
08/2005 DISTRIBUTION REPORT
SERIES: WAMU 05AR7
WEIGHTED AVERAGE PC RATE: 4.94343%
WEIGHTED AVERAGE MATURITY: 357.12752
WEIGHTED AVERAGE LOAN AGE: 2.38769
POOL NUMBER: ALL
ISSUE DATE: 06/23/2005
CERTIFICATE BALANCE AT ISSUE: $851,694,372.45
	TOTAL NUMBER OF MORTAGES	CERTIFICATE ACCOUNT ACTIVITY (@ PCRATE)	CERTIFICATE BALANCE OUTSTANDING
BALANCES FROM LAST FISCAL MONTH-END:	1309		$823,124,553.97
PRINCIPAL POOL COLLECTION(S):
Scheduled Principal Collection Due Current Month		$66,632.10
Unscheduled Principal Collection/Reversals		$3,671,762.17
Liquidations-in-full	20	$13,916,811.21
Subsequent Recoveries		$0.00
Net principal Distributed		$17,655,205.48	-$17,655,205.48

CAPITAL LOSS (PRINCIPAL WRITTEN OFF):			$0.00

BALANCE CURRENT FISCAL MONTH-END:	1289		$805,469,348.49

SCHEDULED INTEREST AT MORTGAGE RATE:		$3,682,406.62

UNSCHEDULED INTEREST AT MORTGAGE RATE:
Unscheduled Interest Collection/Reversals		$0.00
Interest Uncollected on Liquidation		$0.00
Interest Uncollected on Non-Earning Assets		$0.00
Interest Uncollected on Prepayment		$0.00
Uncompensated Uncollected Interest		$0.00
Net Unscheduled Interest Distributed		$0.00

OTHER:
Loan Conversion Fees		$0.00
Expense Reimbursements		$0.00
Gain on Liquidations		$0.00
Hazard Insurance Premium Refunds		$0.00
Recoveries Carried Forward		$0.00
Net Other Distributions		$0.00

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
MASTER SERVICING
MORTGAGE PASS-THROUGH CERTIFICATES
08/2005 DISTRIBUTION REPORT
	TOTAL NUMBER OF MORTAGES	CERTIFICATE ACCOUNT ACTIVITY (@ PCRATE)	CERTIFICATE BALANCE OUTSTANDING
SCHEDULED SERVICING FEE EXPENSES:		$291,523.33

UNSCHEDULED SERVICING FEES:
Unscheduled Service Fee Collections/Reversals		$0.00
Servicing Fees Uncollected on Liquidation		$0.00
Servicing Fees Uncollected/Non-Earning Assets		$0.00
Net Unscheduled Service Fees Distributed		$0.00

MISCELLANEOUS EXPENSES:		$0.00

NET FUNDS DISTRIBUTED:		$21,046,088.77

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005

Distribution by Group
Pool ID		Principal		Interest		Total
Pool - 2750		$17,655,205.48		$3,390,883.29		$21,046,088.77
Aggregate		$17,655,205.48		$3,390,883.29		$21,046,088.77

Number of Loans and Aggregate Principal Balance By Group
Pool ID	Beg Bal	Beg Count	Paid Off / Liq Count	Rem Count	Sched Prin End Bal	Sched Prin	Prin PrePay / Liq	Unsched Prin / Rev	Total Prin
Pool - 2750	$823,124,553.97	1309	20	1289	$805,469,348.49	$66,632.10	$13,916,811.21	$3,671,762.17	$17,655,205.48
Aggregate	$823,124,553.97	1309	20	1289	$805,469,348.49	$66,632.10	$13,916,811.21	$3,671,762.17	$17,655,205.48

Delinquency Information by Group
Pool ID	1 Month Count	Sched End Balance	2 Months Count	Sched End Balance	3 Months Count	Sched End Balance	4 Months Count	Sched End Balance
Pool - 2750	12	$8,988,369.15	0	$0.00	0	$0.00	0	$0.00
Aggregate	12	$8,988,369.15	0	$0.00	0	$0.00	0	$0.00

Foreclosure and REO Information by Group
Pool ID		Foreclosure Count		Sched End Balance		REO Count		Sched End Balance
Pool - 2750		0		$0.00		0		$0.00
Aggregate		0		$0.00		0		$0.00

Aggregate Loss Amounts by Group
Pool ID			Count			Loss Amount
Pool - 2750			0			$0.00
Aggregate			0			$0.00

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005

INSURANCE RESERVES - Group 1
Insurance Type	Original Balance	Claims In Progress	Claims Paid	Coverage Adjustments	Coverage Remaining
MPI	$0.00	$0.00	$0.00	$0.00	$0.00
Special Hazard	$0.00	$0.00	$0.00	$0.00	$0.00
Bankruptcy Bond
Single-Units	$0.00	$0.00	$0.00	$0.00	$0.00
Multi-Units	$0.00	$0.00	$0.00	$0.00	$0.00
Mortgage Repurchase	$0.00	$0.00	$0.00	$0.00	$0.00

INSURANCE RESERVES - Aggregate
Insurance Type	Original Balance	Claims In Progress	Claims Paid	Coverage Adjustments	Coverage Remaining
MPI	$0.00	$0.00	$0.00	$0.00	$0.00
Special Hazard	$0.00	$0.00	$0.00	$0.00	$0.00
Bankruptcy Bond
Single-Units	$0.00	$0.00	$0.00	$0.00	$0.00
Multi-Units	$0.00	$0.00	$0.00	$0.00	$0.00
Mortgage Repurchase	$0.00	$0.00	$0.00	$0.00	$0.00

WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.
Series: WAMU.05AR7
Distribution Date: 08/25/2005

The Subordinate Certificates provide, to the limited extent described in the Prospectus Supplement, credit support, to certain Senior Certificates. The "Prospectus Supplement" is that certain Prospectus Supplement, dated June 21, 2005 to that certain Prospectus Supplement, dated April 20, 2005, to which certain Senior Certificates were offered.



The Class Principal Balances of each Class of the Class B1,B2,B3,B4,B5,B6 Certificatesimmediately after the principal and interest distribution on 200508 are as follows:

Class			Class Principal Balance
B1			$18,735,115.71
B2			$6,387,016.71
B3			$3,832,410.00
B4			$3,406,475.57
B5			$2,554,606.72
B6			$1,702,010.42
Total			$36,617,635.13
Capitalized items used but not defined herein have the meanings ascribed to them in the Prospectus Supplement.

WaMu Mortgage Pass-Through Certificates, Series 2005-AR7 8-K