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 25, 2004

STRUCTURED ASSET SECURITIES CORPORATION (as Depositor under the Trust Agreement dated as of May 1, 2004, providing for the issuance of Structured Asset Securities Corporation Mortgage Pass-Through Certificates, Series 2004-11XS)
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction
of incorporation)

333-106925
(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 2004-11XS, which was made on August 25, 2004.

Section 9 - Financial Statements and Exhibits

Item 9.01 Financial Statements and Exhibits.

99.1 Monthly distribution report pursuant to Section 4.03 of the Trust Agreement for the distribution on August 25, 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 30, 2004

Structured Asset Securities Corporation

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Reporting Package Table of Contents

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Administrator:
Peter Sablich 312.904.8162
peter.sablich@abnamro.com

Analyst:
James Macmillan 714.259.6217
james.macmillan@abnamro.com

Statement Date:

135 S. LaSalle Street, Suite 1625
Chicago, IL 60603
USA

Statements to Certificateholders
Component Detail Report
Cash Reconciliation Summary
Bond Interest Reconciliation

Bond Principal Reconciliation

Other Related Information
Asset-Backed Facts ~ 15 Month Loan Status Summary Part I

Asset-Backed Facts ~ 15 Month Loan Status Summary Part II
Asset-Backed Facts ~ 15 Month Loan Payoff/Loss Summary
Realized Loss Detail

Page 2-3
Page 4
Page 5-7
Page 8

Page 9

Page 10
Page 11-13

Page 14-16
Page 17-19

Page 20-22

Substitution Detail History

Page 23

Page(s)

Information is available for this issue from the following sources

Issue Id:

Monthly Data File
Name:

SAS411XS

SAS411XS_200408_3.ZIP

Closing Date:

First Payment Date:

Rated Final Payment: Date:

28-May-04
25-Jun-04

26-Jun-34

Parties to The Transaction

Depositor: Structured Asset Securities Corporation/Structured Asset Securities Corporation

Underwriter: Lehman Brothers Inc./Lehman Brothers Inc.

Master Servicer: Aurora Loan Services, Inc.

Rating Agency: Moody's Investors Service, Inc./Standard & Poor's

800.246.5761

LaSalle Factor Line

LaSalle Web Site

Servicer Web Site

www.alservices.com

www.etrustee.net

Page 1 of 23

Class

CUSIP

Original

Opening

Principal

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

WAC:
WAMM:
Current Index:
Next Index:

Payment Date:
Prior Payment:
Next Payment:
Record Date:

6.624098%

1.450000%
1.615000%

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Structured Asset Securities Corporation

Mortgage Pass-Through Certificates

Series 2004-11XS

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

344

REMIC III

Statement Date:

ABN AMRO Acct: 721843.3

896.397619385

45.236772308

0.000000000

851.160847077

1.172786923

1.735000000%

0.00

0.000000000

1.57000000%

0.000000000

86359BTX9

I-A1A

65,000,000.00

58,265,845.26

2,940,390.20

0.00

55,325,455.06

76,231.15

896.397619436

45.236772274

0.000000000

851.160847162

1.195196797

1.765000000%

0.00

0.000000000

1.60000000%

0.000000000

86359BTY7

I-A1B

63,695,000.00

57,096,046.37

2,881,356.21

0.00

54,214,690.16

76,128.06

896.397619130

45.236772174

0.000000000

851.160846957

2.151353913

Fixed

0.00

0.000000000

2.88000000%

0.000000000

86359BTZ4

I-A1C

11,500,000.00

10,308,572.62

520,222.88

0.00

9,788,349.74

24,740.57

1000.000000000

0.000000000

1000.000000000

3.525000268

Fixed

0.00

0.000000000

4.23000000%

0.000000000

86359BUA7

I-A2

18,635,000.00

0.00

18,635,000.00

65,688.38

1000.000000000

0.000000000

1000.000000000

3.966666452

Fixed

0.00

0.000000000

4.76000000%

0.000000000

86359BUB5

I-A3A

15,500,000.00

0.00

15,500,000.00

61,483.33

1000.000000000

0.000000000

1000.000000000

4.066666566

Fixed

0.00

0.000000000

4.88000000%

0.000000000

86359BUC3

I-A3B

33,011,000.00

0.00

33,011,000.00

134,244.73

1000.000000000

0.000000000

1000.000000000

4.866666764

Fixed

0.00

0.000000000

5.84000000%

0.000000000

86359BUD1

I-A4A

34,279,000.00

0.00

34,279,000.00

166,824.47

1000.000000000

0.000000000

1000.000000000

4.758333000

Fixed

0.00

0.000000000

5.71000000%

0.000000000

86359BVC2

I-A4B

10,000,000.00

0.00

10,000,000.00

47,583.33

1000.000000000

0.000000000

1000.000000000

5.208333206

Fixed

0.00

0.000000000

6.25000000%

0.000000000

86359BUE9

I-A5A

13,115,000.00

0.00

13,115,000.00

68,307.29

1000.000000000

0.000000000

1000.000000000

5.208333641

Fixed

0.00

0.000000000

6.25000000%

0.000000000

86359BUF6

I-A5B

16,263,000.00

0.00

16,263,000.00

84,703.13

1000.000000000

0.000000000

1000.000000000

4.650000000

Fixed

0.00

0.000000000

5.58000000%

0.000000000

86359BUG4

I-A6

31,222,000.00

0.00

31,222,000.00

145,182.30

918.207500857

28.129241052

0.000000000

890.078259805

2.142483964

Fixed

0.00

0.000000000

2.80000000%

0.000000000

86359BUH2

II-A1

20,423,000.00

18,752,551.79

574,483.49

0.00

18,178,068.30

43,755.95

1000.000000000

0.000000000

1000.000000000

4.500000000

Fixed

0.00

0.000000000

5.40000000%

0.000000000

86359BUJ8

II-A2

71,052,000.00

0.00

71,052,000.00

319,734.00

1000.000000000

0.000000000

1000.000000000

5.000000000

Fixed

0.00

0.000000000

6.00000000%

0.000000000

86359BUK5

I-M1

7,950,000.00

0.00

7,950,000.00

39,750.00

1000.000000000

0.000000000

1000.000000000

5.000000000

Fixed

0.00

0.000000000

6.00000000%

0.000000000

86359BUN9

I-M2

5,963,000.00

0.00

5,963,000.00

29,815.00

1000.000000000

0.000000000

1000.000000000

4.375000000

Fixed

0.00

0.000000000

5.25000000%

0.000000000

86359BUL3

II-M1

1,386,000.00

0.00

1,386,000.00

6,063.75

Page 2 of 23

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

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

WAC:
WAMM:
Current Index:
Next Index:

Payment Date:
Prior Payment:
Next Payment:
Record Date:

6.624098%

1.450000%
1.615000%

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Structured Asset Securities Corporation

Mortgage Pass-Through Certificates

Series 2004-11XS

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

344

REMIC III

Statement Date:

ABN AMRO Acct: 721843.3

1000.000000000

0.000000000

1000.000000000

4.375000000

Fixed

0.00

0.000000000

5.25000000%

0.000000000

86359BVD0

II-M2

1,386,000.00

0.00

1,386,000.00

6,063.75

1000.000000000

0.000000000

1000.000000000

5.039516657

Fixed

0.00

0.000000000

6.04741960%

0.000000000

86359BUM1

5,193,000.00

0.00

5,193,000.00

26,170.21

1000.000000000

0.000000000

1000.000000000

122970.000000000

N/A

0.00

6,148.50

122970.000000000

0.00000000%

0.000000000

9ABSR037

1-P

50.00

0.00

50.00

6,148.50

1000.000000000

0.000000000

1000.000000000

0.000000000

N/A

0.00

0.000000000

0.00000000%

0.000000000

9ABSR038

2-P

50.00

0.00

50.00

0.00

960.655100603

0.000000000

941.510553862

2.113580756

2.468348018%

0.00

0.000000000

2.64017431%

0.000000000

9ABSQ833

1-X

331,267,664.16

318,233,971.24

0.00

311,892,001.96

700,160.96

0.000000000

0.00

0.000000000

N/A

0.000000000

9ABSQ834

LT1-R

0.00

0.000000000

0.00

0.000000000

N/A

0.000000000

9ABSQ835

LT2-R

0.00

Total P&I Payment

0.00

6,148.50

425,573,100.00

409,378,116.04

9,045,231.64

Total

402,461,663.26

6,916,452.78

0.00

2,128,778.86

Page 3 of 23

Class

CUSIP

Original

Opening

Principal

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Structured Asset Securities Corporation

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

Statement Date:

Component Detail

1000.000000000

0.000000000

1000.000000000

5.208333736

Fixed

0.00

0.000000000

6.25000000%

0.000000000

I-M3

4,141,000.00

0.00

4,141,000.00

21,567.71

1000.000000000

0.000000000

1000.000000000

4.375000000

Fixed

0.00

0.000000000

5.25000000%

0.000000000

II-M3

1,052,000.00

0.00

1,052,000.00

4,602.50

Page 4 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Statement Date:

Cash Reconciliation Summary

Current Scheduled Interest

Interest Summary

Less Deferred Interest

Plus Gross Advance Interest

Less PPIS Reducing Scheduled Int

560,063.59

0.00
0.00

Less ASER Interest Adv Reduction

0.00

Less Other Adjustment

0.00

Total

2,199,560.00

Unscheduled Interest:
Prepayment Penalties

6,148.50

Yield Maintenance Penalties

0.00

Other Interest Proceeds

0.00

Total

6,148.50

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

Recoup of Prior Advances

Misc. Fees & Expenses

Total Unscheduled Fees & Expenses
Total Interest Due Trust

Less Fees & Expenses Paid By/To Trust
Trustee Fee
Fee Strips
Misc. Fees
Interest Reserve Withholding

Plus Interest Reserve Deposit
Total

Total Interest Due Certs

Principal Summary

Scheduled Principal:
Current Scheduled Principal
Advanced Scheduled Principal
Scheduled Principal
Unscheduled Principal:
Curtailments
Prepayments in Full
Liquidation Proceeds
Repurchase Proceeds
Other Principal Proceeds
Total Unscheduled Principal
Remittance Principal

Remittance P&I Due Trust

Remittance P&I Due Certs

Pool Balance Summary

Beginning Pool
Scheduled Principal
Unscheduled Principal
Deferred Interest
Liquidations
Repurchases

Ending Pool

Balance

Count

Principal

Interest

Prior Outstanding
Plus Current Period
Less Recovered

Ending Outstanding

Servicing Fee Summary

Current Servicing Fees
Plus Fees Advanced for PPIS
Less Reduction for PPIS
Plus Delinquent Servicing Fees

Total Servicing Fees

Overcollateralization Summary

PPIS Summary

Gross PPIS
Reduced by PPIE
Reduced by Shortfalls in Fees
Reduced by Other Amounts

PPIS Reducing Scheduled
Interest

PPIS Reducing Servicing Fee
PPIS Due Certificate

0.00

0.00
0.00

0.00

2,183,307.12

0.00
0.00
0.00
0.00

0.00

59,322.62

200,808.09
260,130.71

77,875.20

6,528,124.61

0.00
0.00
0.00

6,605,999.81
6,866,130.52

9,049,437.64

412,259,457.82

1,741

260,130.71

6,605,999.81

0.00
0.00

0.00

405,393,327.30

1,719

218,081.17

1,843,230.29

200,808.09

1,639,496.41

210,982.41

1,726,918.44

22,401.38

0.00
0.00

76,146.01

98,547.39

0.00
0.00
0.00
0.00
0.00
0.00

0.00

Advance Summary (Advance Made by Servicer)

)

(22,401.38

2,183,307.12

Interest Not Advanced (

Current Period

)

0.00

1,639,496.41

Workout Fees
Liquidation Fees

0.00
0.00

Less Non Recovered

)

(1,755,808.26

)

(207,906.85

0.00

Overcollateralization Amount

Overcollateralization Deficiency

2,931,764.04

0.00

Other Principal Information

Principal Remittance Amount

Overcollateralization Release Amount

6,866,130.52

110,177.79

6,976,308.31

Principal Distribution Amount

Page 5 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Statement Date:

Cash Reconciliation Summary Pool I

Current Scheduled Interest

Interest Summary

Less Deferred Interest

Plus Gross Advance Interest

Less PPIS Reducing Scheduled Int

439,631.53

0.00
0.00

Less ASER Interest Adv Reduction

0.00

Less Other Adjustment

0.00

Total

1,763,775.35

Unscheduled Interest:
Prepayment Penalties

6,148.50

Yield Maintenance Penalties

0.00

Other Interest Proceeds

0.00

Total

6,148.50

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

Recoup of Prior Advances

Misc. Fees & Expenses

Total Unscheduled Fees & Expenses
Total Interest Due Trust

Less Fees & Expenses Paid By/To Trust
Trustee Fee
Fee Strips
Misc. Fees
Interest Reserve Withholding

Plus Interest Reserve Deposit
Total

Total Interest Due Certs

Principal Summary

Remittance P&I Due Trust

Remittance P&I Due Certs

Pool Balance Summary

Beginning Pool
Scheduled Principal
Unscheduled Principal
Deferred Interest
Liquidations
Repurchases

Ending Pool

Balance

Count

Principal

Interest

Prior Outstanding
Plus Current Period
Less Recovered

Ending Outstanding

Servicing Fee Summary

Current Servicing Fees
Plus Fees Advanced for PPIS
Less Reduction for PPIS
Plus Delinquent Servicing Fees

Total Servicing Fees

Overcollateralization Summary

PPIS Summary

Gross PPIS
Reduced by PPIE
Reduced by Shortfalls in Fees
Reduced by Other Amounts

PPIS Reducing Scheduled
Interest

PPIS Reducing Servicing Fee
PPIS Due Certificate

0.00

0.00
0.00

0.00

1,752,764.91

0.00
0.00
0.00
0.00

0.00

45,825.32

148,909.28
194,734.60

48,208.71

6,099,025.97

0.00
0.00
0.00

6,147,234.68
6,341,969.28

8,094,734.19

318,233,971.24

1,578

194,734.60

6,147,234.68

0.00
0.00

0.00

311,892,001.96

1,557

163,830.18

1,483,133.27

148,909.28

1,324,143.82

159,083.60

1,411,565.85

17,158.94

0.00
0.00

61,799.80

78,958.74

0.00
0.00
0.00
0.00
0.00
0.00

0.00

Advance Summary (Advance Made by Servicer)

)

(17,158.94

1,752,764.91

Interest Not Advanced (

Current Period

)

0.00

1,324,143.82

Workout Fees
Liquidation Fees

0.00
0.00

Less Non Recovered

)

(1,395,711.24

)

(153,655.86

0.00

Overcollateralization Amount

Overcollateralization Deficiency

2,484,507.00

0.00

Other Principal Information

Principal Remittance Amount

Overcollateralization Release Amount

6,341,969.28

0.00

6,341,969.28

Principal Distribution Amount

Page 6 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Statement Date:

Cash Reconciliation Summary Pool II

Current Scheduled Interest

Interest Summary

Less Deferred Interest

Plus Gross Advance Interest

Less PPIS Reducing Scheduled Int

120,432.06

0.00
0.00

Less ASER Interest Adv Reduction

0.00

Less Other Adjustment

0.00

Total

435,784.65

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

Recoup of Prior Advances

Misc. Fees & Expenses

Total Unscheduled Fees & Expenses
Total Interest Due Trust

Less Fees & Expenses Paid By/To Trust
Trustee Fee
Fee Strips
Misc. Fees
Interest Reserve Withholding

Plus Interest Reserve Deposit
Total

Total Interest Due Certs

Principal Summary

Remittance P&I Due Trust

Remittance P&I Due Certs

Pool Balance Summary

Beginning Pool
Scheduled Principal
Unscheduled Principal
Deferred Interest
Liquidations
Repurchases

Ending Pool

Balance

Count

Principal

Interest

Prior Outstanding
Plus Current Period
Less Recovered

Ending Outstanding

Servicing Fee Summary

Current Servicing Fees
Plus Fees Advanced for PPIS
Less Reduction for PPIS
Plus Delinquent Servicing Fees

Total Servicing Fees

Overcollateralization Summary

PPIS Summary

Gross PPIS
Reduced by PPIE
Reduced by Shortfalls in Fees
Reduced by Other Amounts

PPIS Reducing Scheduled
Interest

PPIS Reducing Servicing Fee
PPIS Due Certificate

0.00

0.00
0.00

0.00

430,542.21

0.00
0.00
0.00
0.00

0.00

13,497.30
51,898.81
65,396.11

29,666.49

429,098.64

0.00
0.00
0.00

458,765.13
524,161.24

954,703.45

94,025,486.58

163

65,396.11

458,765.13

0.00
0.00

0.00

93,501,325.34

162

54,250.99

360,097.02

51,898.81

315,352.59

51,898.81

315,352.59

5,242.44

0.00
0.00

14,346.20

19,588.64

0.00
0.00
0.00
0.00
0.00
0.00

0.00

Advance Summary (Advance Made by Servicer)

)

(5,242.44

430,542.21

Interest Not Advanced (

Current Period

)

0.00

315,352.59

Workout Fees
Liquidation Fees

0.00
0.00

Less Non Recovered

)

(360,097.02

)

(54,250.99

0.00

Overcollateralization Amount

Overcollateralization Deficiency

447,257.04

0.00

Other Principal Information

Principal Remittance Amount

Overcollateralization Release Amount

524,161.24
110,177.79

634,339.03

Principal Distribution Amount

Page 7 of 23

Structured Asset Securities Corporation

Class

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Bond Interest Reconciliation

Additions

Accrual

Method Days

Statement Date:

Accrued

Certificate

Interest

Deposits
from YM

Agreement

Prior

Int Carry-Fwd

Shortfall

Prior

Shortfall

Reimbursement

Other

Interest

Proceeds

Other

Interest

Losses

Current

Int Carry-Fwd

Shortfall

Current Basis

Risk Carry-Fwd

Shortfall

Remaining

Int Carry-Fwd

Shortfall

Remaining Basis

Risk Carry-Fwd

Shortfall

Net Cap Rate

in Effect

Y/N

Distributable

Certificate

Interest

Payment

Amount

Deductions

Outstanding

0.00

1-P

6,148.50

30/360

0.00

1-X

2,195,209.80

700,160.96

1,495,048.84

0.00

700,160.96

0.00

0.01

1,495,048.85

0.00

2-P

0.00

30/360

0.00

I-A1A

76,231.15

Act/360

0.00

76,231.15

0.00

I-A1B

76,128.06

Act/360

0.00

76,128.06

0.00

I-A1C

24,740.57

30/360

0.00

24,740.57

0.00

I-A2

65,688.38

30/360

0.00

65,688.38

0.00

I-A3A

61,483.33

30/360

0.00

61,483.33

0.00

I-A3B

134,244.73

30/360

0.00

134,244.73

0.00

I-A4A

166,824.47

30/360

0.00

166,824.47

0.00

I-A4B

47,583.33

30/360

0.00

47,583.33

0.00

I-A5A

68,307.29

30/360

0.00

68,307.29

0.00

I-A5B

84,703.13

30/360

0.00

84,703.13

0.00

I-A6

145,182.30

30/360

0.00

145,182.30

0.00

II-A1

43,755.95

30/360

0.00

43,755.95

0.00

II-A2

319,734.00

30/360

0.00

319,734.00

0.00

II-M1

6,063.75

30/360

0.00

6,063.75

0.00

II-M2

6,063.75

30/360

0.00

6,063.75

0.00

I-M1

39,750.00

30/360

0.00

39,750.00

0.00

I-M2

29,815.00

30/360

0.00

29,815.00

0.00

26,170.21

30/360

0.00

26,170.21

0.00

1,495,048.84

2,122,630.36

3,623,827.70

2,128,778.86

0.00

0.01

1,495,048.85

0.00

(2) Interest Carry-Forward Shortfall is unpaid interest with interest thereon
(3) Basis Risk Carry-Forward Shortfall - difference between LIBOR plus margin and the Net Rate Cap.

Page 8 of 23

(1) Other Interest Proceeds are additional interest amounts specifically allocated to the bond(s) and used in determining the bonds Distributable Interest.

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Bond Principal Reconciliation

Credit Support

Original

Current(4)

ABN AMRO

LaSalle Bank

N.A.

Statement Date:

Beginning

Class Balance

Unscheduled

Principal

Payment

Extra

Principal

Payment Amt

Prior

Loss

Reimburs.

Rated

Final

Maturity

Class

Current

Losses

Original

Class Balance

Scheduled

Principal

Payment

Ending

Class Balance

Cumulative

Losses

Interest on

Losses

Additions

Losses

I-A1A

57.55%

61.43%

6/26/2034

55,325,455.06

0.00

58,265,845.26

65,000,000.00

90,286.74

0.00

2,850,103.46

I-A1B

57.55%

61.43%

6/26/2034

54,214,690.16

0.00

57,096,046.37

63,695,000.00

88,474.06

0.00

2,792,882.15

I-A1C

57.55%

61.43%

6/26/2034

9,788,349.74

0.00

10,308,572.62

11,500,000.00

15,973.81

0.00

504,249.07

I-A2

51.91%

55.41%

6/26/2034

18,635,000.00

0.00

18,635,000.00

0.00

I-A3A

37.22%

39.73%

6/26/2034

15,500,000.00

0.00

15,500,000.00

0.00

I-A3B

37.22%

39.73%

6/26/2034

33,011,000.00

0.00

33,011,000.00

0.00

I-A4A

23.81%

25.42%

6/26/2034

34,279,000.00

0.00

34,279,000.00

0.00

I-A4B

23.81%

25.42%

6/26/2034

10,000,000.00

0.00

10,000,000.00

0.00

I-A5A

14.92%

15.93%

6/26/2034

13,115,000.00

0.00

13,115,000.00

0.00

I-A5B

14.92%

15.93%

6/26/2034

16,263,000.00

0.00

16,263,000.00

0.00

I-A6

5.47%

5.84%

6/26/2034

31,222,000.00

0.00

31,222,000.00

0.00

II-A1

4.01%

4.11%

6/26/2034

18,178,068.30

0.00

18,752,551.79

20,423,000.00

65,396.11

0.00

160,500.04

348,587.34

II-A2

4.01%

4.11%

6/26/2034

71,052,000.00

0.00

71,052,000.00

0.00

I-M1

3.06%

3.27%

6/26/2034

7,950,000.00

0.00

7,950,000.00

0.00

I-M2

1.25%

1.34%

6/26/2034

5,963,000.00

0.00

5,963,000.00

0.00

II-M1

2.56%

2.62%

6/26/2034

1,386,000.00

0.00

1,386,000.00

0.00

II-M2

1.10%

1.13%

6/26/2034

1,386,000.00

0.00

1,386,000.00

0.00

6/26/2034

5,193,000.00

0.00

5,193,000.00

0.00

1-P

6/26/2034

50.00

0.00

50.00

0.00

2-P

6/26/2034

50.00

0.00

50.00

0.00

1-X

6/26/2034

311,892,001.96

0.00

318,233,971.24

331,267,664.16

0.00

727,612,087.28

0.00

6/26/2034

0.00

260,130.72

0.00

6,495,822.01

160,500.05

425,573,100.00

402,461,663.26

Page 9 of 23

(1) Extra Principal Amounts: the lessor of (i) the excess, if any, of the overcollateralization Target Amount over the Overcollateralization Amount.

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Other Related Information

Statement Date:

$4,206.00

Insurance Premium......................................................................................................................

Insured Payments to Class:

I-A2B............................................................................................................................

I-A3B...............................................................................................................................

I-A5...................................................................................................................................

I-A6..................................................................................................................................

0.00

Page 10 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Part I

Distribution

Date

REO

Balance

Statement Date:

Foreclosure

Delinq 3+ Months

Delinq 2 Months

Delinq 1 Month

Current

Balance

Delinquency Aging Categories

2.85%

2.14%

0.47%

0.25%

0.52%

1,647,735

0.41%

0.00%

25-Aug-04

8,663,539

1,003,512

1,653

394,078,541

96.16%

97.21%

2.93%

2.20%

0.75%

0.72%

0.17%

467,646

0.11%

0.00%

26-Jul-04

9,069,478

2,949,390

1,674

399,772,944

96.15%

96.97%

1.53%

1.08%

0.17%

0.07%

0.00%

25-Jun-04

4,511,386

309,789

1,737

414,600,531

98.30%

98.85%

Page 11 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Part I

Distribution

Date

REO

Balance

Statement Date:

Foreclosure

Delinq 3+ Months

Delinq 2 Months

Delinq 1 Month

Current

Balance

Delinquency Aging Categories

Pool I

3.15%

2.78%

0.51%

0.32%

0.58%

1,647,735

0.53%

0.00%

25-Aug-04

8,663,539

1,003,512

1,491

300,577,215

95.76%

96.37%

3.23%

2.85%

0.82%

0.93%

0.19%

467,646

0.15%

0.00%

26-Jul-04

9,069,478

2,949,390

1,511

305,747,458

95.75%

96.08%

1.62%

1.23%

0.19%

0.10%

0.00%

25-Jun-04

4,000,986

309,789

1,574

320,409,052

98.19%

98.67%

Page 12 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Part I

Distribution

Date

REO

Balance

Statement Date:

Foreclosure

Delinq 3+ Months

Delinq 2 Months

Delinq 1 Month

Current

Balance

Delinquency Aging Categories

Pool II

0.00%

25-Aug-04

162

93,501,325

100.00%

0.00%

26-Jul-04

163

94,025,487

100.00%

0.61%

0.54%

0.00%

25-Jun-04

510,400

163

94,191,479

99.39%

99.46%

Page 13 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Distribution

Date

Statement Date:

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance # Balance

# Balance

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance # Balance

# Balance

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance

# Balance

In Foreclosure and Delinquent

In Bankruptcy and Delinquent

In REO and Delinquent

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Part II

25-Aug-04

0.00%

0.00% 0.00%

0.00%

0.17%

0.07%

273,525

0.00%

26-Jul-04

0.00%

0.00% 0.00%

0.00%

25-Jun-04

0.00%

0.00% 0.00%

0.00%

Page 14 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Distribution

Date

Statement Date:

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance # Balance

# Balance

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance # Balance

# Balance

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance

# Balance

In Foreclosure and Delinquent

In Bankruptcy and Delinquent

In REO and Delinquent

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Part II - Pool I

25-Aug-04

0.00%

0.00% 0.00%

0.00%

0.19%

0.09%

273,525

0.00%

26-Jul-04

0.00%

0.00% 0.00%

0.00%

25-Jun-04

0.00%

0.00% 0.00%

0.00%

Page 15 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Distribution

Date

Statement Date:

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance # Balance

# Balance

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance # Balance

# Balance

Current 31 - 60 Days 61 - 90 Days

90 + Days

# Balance # Balance

# Balance

In Foreclosure and Delinquent

In Bankruptcy and Delinquent

In REO and Delinquent

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Part II - Pool II

25-Aug-04

0.00%

0.00% 0.00%

0.00%

26-Jul-04

0.00%

0.00% 0.00%

0.00%

25-Jun-04

0.00%

0.00% 0.00%

0.00%

Page 16 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary

Distribution

Date

Ending Pool (1)

Payoffs(2)

Realized Losses (2)

Remaining Term

Curr Weighted Avg.

# Balance

# Amount

Life

Coupon Remit

Statement Date:

Ending Arrearage (1)

Balance

Insurance

Substitution

Liquidation

Proceeds

Pool II

25-Aug-04

1,719

95.98%

405,393,327

94.97%

1.26%

1.58%

0.00%

344

6.62%

6.34%

6,528,125

0.00

26-Jul-04

1,741

97.21%

412,259,458

96.58%

1.47%

1.52%

0.00%

345

6.64%

6.35%

6,374,719

0.00

25-Jun-04

1,767

98.66%

419,421,706

98.26%

1.34%

1.62%

0.00%

345

6.65%

6.36%

6,921,413

0.00

(1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period.

Page 17 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary

Distribution

Date

Ending Pool (1)

Payoffs(2)

Realized Losses (2)

Remaining Term

Curr Weighted Avg.

# Balance

# Amount

Life

Coupon Remit

Statement Date:

Ending Arrearage (1)

Balance

Insurance

Substitution

Liquidation

Proceeds

Pool I

25-Aug-04

1,557

86.93%

311,892,002

73.07%

1.33%

1.92%

0.00%

341

6.88%

6.59%

6,099,026

0.00

26-Jul-04

1,578

88.11%

318,233,971

74.55%

1.56%

1.78%

0.00%

342

6.90%

6.60%

5,776,572

0.00

25-Jun-04

1,603

89.50%

324,719,827

76.07%

1.35%

1.85%

0.00%

342

6.91%

6.61%

6,119,905

0.00

(1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period.

Page 18 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary

Distribution

Date

Ending Pool (1)

Payoffs(2)

Realized Losses (2)

Remaining Term

Curr Weighted Avg.

# Balance

# Amount

Life

Coupon Remit

Statement Date:

Ending Arrearage (1)

Balance

Insurance

Substitution

Liquidation

Proceeds

Pool II

25-Aug-04

162

9.05%

93,501,325

21.90%

0.61%

0.46%

0.00%

354

5.74%

5.49%

429,099

0.00

26-Jul-04

163

9.10%

94,025,487

22.03%

0.61%

0.63%

0.00%

355

5.75%

5.50%

598,147

0.00

25-Jun-04

164

9.16%

94,701,879

22.19%

1.20%

0.84%

0.00%

356

5.75%

5.50%

801,508

0.00

(1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period.

Page 19 of 23

Structured Asset Securities Corporation

Payment Date:
Prior Payment:
Next Payment:
Record Date:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Realized Loss Detail

Period

Disclosure

Control #

Appraisal

Date

Appraisal

Value

Beginning
Scheduled

Balance

Gross

Proceeds

Gross Proceeds

as a % of

Sched. Balance

Aggregate

Liquidation

Expenses *

Net

Liquidation

Proceeds

Net Proceeds

as a % of

Sched. Balance

Realized

Loss

Statement Date:

Current Total
Cumulative

Page 20 of 23

* 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:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Realized Loss Detail

Period

Disclosure

Control #

Appraisal

Date

Appraisal

Value

Beginning
Scheduled

Balance

Gross

Proceeds

Gross Proceeds

as a % of

Sched. Balance

Aggregate

Liquidation

Expenses *

Net

Liquidation

Proceeds

Net Proceeds

as a % of

Sched. Balance

Realized

Loss

Statement Date:

Pool I

Current Total
Cumulative

Page 21 of 23

* 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:

25-Aug-04
25-Aug-04

26-Jul-04

27-Sep-04

30-Jul-04

Mortgage Pass-Through Certificates

Series 2004-11XS

ABN AMRO Acct: 721843.3

Realized Loss Detail

Period

Disclosure

Control #

Appraisal

Date

Appraisal

Value

Beginning
Scheduled

Balance

Gross

Proceeds

Gross Proceeds

as a % of

Sched. Balance

Aggregate

Liquidation

Expenses *

Net

Liquidation

Proceeds

Net Proceeds

as a % of

Sched. Balance

Realized

Loss

Statement Date:

Pool II

Current Total
Cumulative

Page 22 of 23

* Aggregate liquidation expenses also include outstanding P&I advances and unpaid servicing fees, unpaid trustee fees, etc..

Structured Asset Securities Corporation

Substitution Detail History

ABN AMRO Acct: 721843.3

Series 2004-11XS

Mortgage Pass-Through Certificates

30-Jul-04

27-Sep-04

26-Jul-04

25-Aug-04

Record Date:

Next Payment:

Prior Payment:

Payment Date:

Statement Date:

Property ID

Deleted Loan

Qualified Substitute

Scheduled Prin Bal

Page 23 of 23

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 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 the
Mortgaged Properties.

(A)

Structured Asset Securities Corp Mortgage Pass-through Certificates 2004-11XS 8-K