Banc of America Funding Corporation (BAFC) mortgage pass-through certificates, series 2004-4, are rated by Fitch as follows:

Group 1 certificates:

-- $183,422,865 classes 1-A-1 through 1-A-7, 30-IO, 1-A-R, and 1-A-LR 'AAA' (group 1 senior certificates);

Group 15-year crossed certificates (consisting of groups 2 and 3):

-- $73,449,557 classes 2-A-1, 3-A-1, and 15-IO 'AAA' (group 15-year crossed senior certificates);

-- $522,000 class 15-B-1 'AA';

-- $186,000 class 15-B-2 'A';

-- $112,000 class 15-B-3 'BBB';

-- $111,000 class 15-B-4 'BB';

-- $75,000 class 15-B-5 'B'.

Groups 1 and 15-year crossed certificates:

-- $2,147,765 class X-PO (consisting of classes 1-X-PO, 2-X-PO, and 3-X-PO components) 'AAA';

-- $533,557 class 15-PO (consisting of classes 2-15-PO and 3-15-PO components) 'AAA'.

The 'AAA' rating on the group 1 senior certificates reflects the 3.15% subordination provided by the 1.55% class 30-B-1, the 0.70% class 30-B-2, the 0.30% class 30-B-3, the 0.30% privately offered class 30-B-4, the 0.15% privately offered class 30-B-5, and the 0.15% privately offered class 30-B-6.

The 'AAA' rating on the group 15-year crossed senior certificates reflects the 1.45% subordination provided by the 0.70% class 15-B-1, the 0.25% class 15-B-2, the 0.15% class 15-B-3, the 0.15% privately offered class 15-B-4, the 0.10% privately offered class 15-B-5, and the 0.10% privately offered class 15-B-6.

Fitch believes the amount of credit enhancement will be sufficient to cover credit losses. The ratings also reflect the high quality of the underlying collateral purchased by Banc of America Funding Corporation, the integrity of the legal and financial structures, and the master servicing capabilities of Washington Mutual Mortgage Securities Corp. (rated 'RMS2+' by Fitch) and Wells Fargo Bank, N.A. (rated 'RMS1' by Fitch).

The trust comprises three loan groups of conventional, fixed-rate mortgage loans that are secured by first liens on one- to three-family residential properties. Loan group 1 collateralizes group 1 certificates and components and loan groups 2 and 3 collateralize group 15-year crossed certificates and components. The class X-PO and 15-PO consist of three separate components and two separate components, respectively, that are not severable.

Loan group 1 comprises 378 mortgage loans that have original terms to maturity of approximately 30 years. The aggregate unpaid principal balance of the pool is $189,389,199 as of Nov. 1, 2004 (the cut-off date), and the average principal balance is $501,030. The weighted average original loan-to-value ratio (OLTV) of the loan pool is approximately 68.83%; approximately 4.00% of the loans have an OLTV greater than 80%. The weighted average coupon of the mortgage loans is 6.045%, and the weighted average FICO score is 724. Cash-out and rate/term refinance loans represent 18.61% and 38.40% of the loan pool, respectively. The states that represent the largest geographic concentration are California (49.99%) and New York (9.58%). All other states represent less than 5% of the outstanding balance of the pool.

Loan group 2 comprises 36 mortgage loans that have original terms to maturity of approximately 15 years. The aggregate unpaid principal balance of the pool is $19,179,733 as of the cut-off date, and the average principal balance is $532,770. The weighted average OLTV of the loan pool is approximately 59.83%, and none of the mortgage loans have an OLTV greater than 80%. The weighted average coupon of the mortgage loans is 4.742%, and the weighted average FICO score is 740. Cash-out and rate/term refinance loans represent 15.39% and 74.51% of the loan pool, respectively. The states that represent the largest geographic concentration are Illinois (32.73%), California (11.93%), Texas (7.88%), Connecticut (7.44%), South Carolina (7.20%), North Carolina (7.20%), and Florida (6.94%). All other states represent less than 5% of the outstanding balance of the pool.

Loan group 3 comprises 108 mortgage loans that have original terms to maturity of approximately 15 years. The aggregate unpaid principal balance of the pool is $55,350,872 as of the cut-off date and the average principal balance is $512,508. The weighted average OLTV of the loan pool is approximately 58.89%; approximately 1.52% of the loans have an OLTV greater than 80%. The weighted average coupon of the mortgage loans is 5.114%, and the weighted average FICO score is 733. Cash-out and rate/term refinance loans represent 16.41% and 64.47% of the loan pool, respectively. The states that represent the largest geographic concentration are California (30.55%), Illinois (7.25%), and Florida (6.60%). All other states represent less than 5% of the outstanding balance of the pool.

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.

BAFC, a special purpose corporation, purchased the mortgage loans from various sellers and deposited the loans in the trust, which issued the certificates, representing undivided beneficial ownership in the trust. Wells Fargo Bank, N.A. will serve as master servicer and securities administrator. Wachovia Bank, N.A. will serve as trustee. For federal income tax purposes, an election will be made to treat the trust as multiple real estate mortgage investment conduits (REMICs).