Fitch Rates BOAMSI $733.1MM Series 2004-L.

NEW YORK -- Banc of America Mortgage Securities, Inc. (BoAMSI), series 2004-L, mortgage pass-through certificates, are rated by Fitch Ratings as follows:

--$709,934,100 classes 1-A-1, 1-A-R, 1-A-LR, 2-A-1, 3-A-1, and 4-A-1 (senior certificates) 'AAA';

--$12,863,000 class B-1 'AA';

--$4,777,000 class B-2 'A';

--$2,940,000 class B-3 'BBB';

--$1,470,000 class B-4 'BB';

--$1,102,000 class B-5 'B'.

The 'AAA' rating on the senior certificates reflects the 3.40% subordination provided by the 1.75% class B-1, the 0.65% class B-2, the 0.40% class B-3, the 0.20% privately offered class B-4, the 0.15% privately offered class B-5, and the 0.25% privately offered class B-6. The ratings on class B-1, B-2, B-3, B-4, and B-5 certificates reflect each certificate's respective level of subordination.

The ratings also reflect the quality of the underlying mortgage collateral, the primary servicing capabilities of Bank of America Mortgage, Inc. (rated 'RPS1' by Fitch) and Fitch's confidence in the integrity of the legal and financial structure of the transaction.

The transaction consists of four groups of adjustable interest rate, fully amortizing mortgage loans, secured by first liens on one- to four-family properties, with a total of 1,376 loans and an aggregate principal balance of $734,924,340.10 as of Dec. 1, 2004 (the cut-off date). The four loan groups are cross-collateralized.

The group 1 collateral consists of 3/1 hybrid adjustable-rate mortgage (ARM) loans. After the initial fixed interest rate period of three years, the interest rate will adjust annually based on the sum of one-year LIBOR index and a gross margin specified in the applicable mortgage note. Approximately 62.19% of group 1 loans require interest-only payments until the month following the first adjustment date. As of the cut-off date, the group has an aggregate principal balance of approximately $131,018,167 and an average balance of $515,820. The weighted average original loan-to-value ratio (OLTV) for the mortgage loans is approximately 71.83%. The weighted average remaining term to maturity (WAM) is 359 months, and the weighted average FICO credit score for the group is 733. Second homes and investor-occupied properties constitute 7.56% and 1.44% of the loans in group 1, respectively. Rate/term and cashout refinances account for 33.28% and 20.56% of the loans in group 1, respectively. The states that represent the largest geographic concentration of mortgaged properties are California (59.26%), Florida (7.14%), and Illinois (6.73). All other states represent less than 5% of the outstanding balance of the group.

The group 2 collateral consists of 5/1 hybrid ARM mortgage loans. After the initial fixed interest rate period of five years, the interest rate will adjust annually based on the sum of one-year LIBOR index and a gross margin specified in the applicable mortgage note. Approximately 61.29% of group 2 loans require interest-only payments until the month following the first adjustment date. As of the cut-off date, the group has an aggregate principal balance of approximately $469,247,002.46 and an average balance of $536,282. The weighted average OLTV for the mortgage loans is approximately 71.14%. The WAM is 359 months, and the weighted average FICO credit score for the group is 736. Second homes and investor-occupied properties constitute 8.25% and 1.05% of the loans in group 2, respectively. Rate/term and cashout refinances account for 27.80% and 15.91% of the loans in group 2, respectively. The states that represent the largest geographic concentration of mortgaged properties are California (58.48%) and Florida (7.53%). All other states represent less than 5% of the outstanding balance of the pool.

The group 3 collateral consists of 7/1 hybrid ARM mortgage loans. After the initial fixed interest rate period of seven years, the interest rate will adjust annually based on the sum of one-year LIBOR index and a gross margin specified in the applicable mortgage note. Approximately 46.33% of group 3 loans require interest-only payments until the month following the first adjustment date. As of the cut-off date, the group has an aggregate principal balance of approximately $51,918,157.68 and an average balance of $519,182. The weighted average OLTV for the mortgage loans is approximately 69.68%. The WAM is 357 months, and the weighted average FICO credit score for the group is 749. Second home properties constitute 6.27% and there are 0.70% investor-occupied properties. Rate/term and cashout refinances account for 23.05% and 20.23% of the loans in group 3, respectively. The states that represent the largest geographic concentration of mortgaged properties are California (53.35%), Virginia (7.76%), Maryland (6.39%), and Texas (5.49%). All other states represent less than 5% of the outstanding balance of the group.

The group 4 collateral consists of a 10/1 hybrid ARM mortgage loans. After the initial fixed interest rate period of 10 years, the interest rate will adjust annually based on the sum of one-year LIBOR index and a gross margin specified in the applicable mortgage note. Approximately 61.64% of group 4 loans require interest-only payments until the month following the first adjustment date. As of the cut-off date, the group has an aggregate principal balance of approximately $82,741,012.26 and an average balance of $562,864. The weighted average OLTV for the mortgage loans is approximately 69.09%. The WAM is 359 months, and the weighted average FICO credit score for the group is 749. Second homes and investor-occupied properties constitute 11.19% and 0.49% of the loans in group 4, respectively. Rate/term and cashout refinances account for 25.71% and 18.88% of the loans in group 4, respectively. The states that represent the largest geographic concentration of mortgaged properties are California (48.61%), Virginia (9.12%), Maryland (7.56%), and Florida (5.30%). All other states represent less than 5% of the outstanding balance of the pool.

Approximately 63.51% of the group 1 mortgage loans, approximately 62.22% of the group 2 mortgage loans, approximately 68.11% of the group 3 mortgage loans, approximately 77.81% of the group 4 mortgage loans, and approximately 64.62% of all of the mortgage loans were originated under the accelerated processing programs. Loans in the accelerated processing programs, which may include the all-ready home and rate reduction refinance programs, are subject to less stringent documentation requirements.

None of the mortgage loans are 'high cost' loans as defined under any local, state, or federal laws. For additional information on Fitch's rating criteria regarding predatory lending legislation, see the press release 'Fitch Revises Rating Criteria in Wake of Predatory Lending Legislation,' dated May 1, 2003, available on the Fitch Ratings web site at www.fitchratings.com.

Banc of America Mortgage Securities, Inc. deposited the loans in the trust, which issued the certificates, representing undivided beneficial ownership in the trust. For federal income tax purposes, elections will be made to treat the trust as two separate real estate mortgage investment conduits (REMICs). Wells Fargo Bank, National Association will act as trustee.