Credit Suisse First Boston Mortgage Securities Corp.
Home Equity Asset Trust Series 2004-4
Mortgage Pass-Through Certificates, HEAT Series 2004-4

STATEMENT TO CERTIFICATEHOLDERS
Section 4.04 of the PSA, dated June 1, 2004

Distribution Date:

27-Sep-04

		Original	Beginning				Interest		Ending
		Certificate	Certificate	Principal	Interest	Realized Loss	Shortfall	Total	Certificate
Class	Cusip	Face Value	Balance (1)	Distribution	Distribution	of Principal	Amount	Distribution	Balance (1)
A-1	437084CS3	$575,000,000.00	$563,767,832.38	$9,156,525.35	$974,143.83	N/A	$0.00	$10,130,669.18	$554,611,307.03
A-2	437084CT1	$132,500,000.00	$129,657,728.91	$3,091,197.20	$229,980.40	N/A	$0.00	$3,321,177.60	$126,566,531.71
A-3	437084CU8	$200,000,000.00	$195,237,855.24	$5,179,213.41	$330,196.02	N/A	$0.00	$5,509,409.43	$190,058,641.83
A-4	437084CV6	$22,000,000.00	$22,000,000.00	$0.00	$42,652.50	N/A	$0.00	$42,652.50	$22,000,000.00
A-IO-1	437084CW4	$306,735,000.00	$300,518,927.45	$0.00	$1,886,189.78	N/A	$0.00	$1,886,189.78	$294,768,038.59
A-IO-2	437084DJ2	$990,000,000.00	$990,000,000.00	$0.00	$0.00	N/A	$0.00	$0.00	$950,000,000.00
A-IO-S	437084DK9	$1,100,000,050.00	$1,081,163,417.31	$0.00	$253,137.78	N/A	$0.00	$253,137.78	$1,066,098,317.78
M-1	437084CZ7	$35,750,000.00	$35,750,000.00	$0.00	$69,965.73	$0.00	$0.00	$69,965.73	$35,750,000.00
M-2	437084DA1	$27,500,000.00	$27,500,000.00	$0.00	$55,836.46	$0.00	$0.00	$55,836.46	$27,500,000.00
M-3	437084DB9	$22,000,000.00	$22,000,000.00	$0.00	$46,282.50	$0.00	$0.00	$46,282.50	$22,000,000.00
M-4	437084DC7	$16,500,000.00	$16,500,000.00	$0.00	$40,308.13	$0.00	$0.00	$40,308.13	$16,500,000.00
M-5	437084DD5	$19,250,000.00	$19,250,000.00	$0.00	$48,790.73	$0.00	$0.00	$48,790.73	$19,250,000.00
M-6	437084DE3	$13,750,000.00	$13,750,000.00	$0.00	$38,631.77	$0.00	$0.00	$38,631.77	$13,750,000.00
B-1	437084DF0	$13,750,000.00	$13,750,000.00	$0.00	$45,564.06	$0.00	$0.00	$45,564.06	$13,750,000.00
B-2	437084DG8	$11,000,000.00	$11,000,000.00	$0.00	$38,972.08	$0.00	$0.00	$38,972.08	$11,000,000.00
B-3	437084DH6	$11,000,000.00	$11,000,000.00	$0.00	$54,097.08	$0.00	$0.00	$54,097.08	$11,000,000.00
X	437084DL7	$1,100,000,050.00	$1,081,163,417.31	$0.00	$3.17	N/A	$0.00	$3.17	$1,066,098,317.78
R	437084CX2	$25.00	$0.00	$0.00	$0.00	N/A	$0.00	$0.00	$0.00
R-II	437084CY0	$25.00	$0.00	$0.00	$0.00	N/A	$0.00	$0.00	$0.00
Total		$1,100,000,050.00	$1,081,163,416.53	$17,426,935.96	$4,154,752.02	$0.00	$0.00	$21,581,687.98	$1,063,736,480.57
(1) Classes A-IO-1, A-IO-2, A-IO-S and X are IO Certs, and the Balances reflected for these Certs are Notional Amounts

			Interest		Ending		Current
	Principal	Interest	Carry-forward	Total	Certificate		Pass-Through
Class	Distribution	Distribution	Amount	Distribution	Balance	Class	Interest Rate
A-1	$15.92439191	$1.69416318	$0.00000000	$17.61855510	$964.54140353	A-1	1.88500%
A-2	$23.32979019	$1.73570113	$0.00000000	$25.06549132	$955.21910725	A-2	1.93500%
A-3	$25.89606705	$1.65098010	$0.00000000	$27.54704715	$950.29320915	A-3	1.84500%
A-4	$0.00000000	$1.93875000	$0.00000000	$1.93875000	$1,000.00000000	A-4	2.11500%
A-IO-1	$0.00000000	$6.14924863	$0.00000000	$6.14924863	$960.98599308	A-IO-1	6.38500%
A-IO-2	$0.00000000	$0.00000000	$0.00000000	$0.00000000	$959.59595960	A-IO-2	0.00000%
A-IO-S	$0.00000000	$0.23012524	$0.00000000	$0.23012524	$969.18024484	A-IO-S	0.28096%
M-1	$0.00000000	$1.95708336	$0.00000000	$1.95708336	$1,000.00000000	M-1	2.13500%
M-2	$0.00000000	$2.03041673	$0.00000000	$2.03041673	$1,000.00000000	M-2	2.21500%
M-3	$0.00000000	$2.10375000	$0.00000000	$2.10375000	$1,000.00000000	M-3	2.29500%
M-4	$0.00000000	$2.44291697	$0.00000000	$2.44291697	$1,000.00000000	M-4	2.66500%
M-5	$0.00000000	$2.53458338	$0.00000000	$2.53458338	$1,000.00000000	M-5	2.76500%
M-6	$0.00000000	$2.80958327	$0.00000000	$2.80958327	$1,000.00000000	M-6	3.06500%
B-1	$0.00000000	$3.31374982	$0.00000000	$3.31374982	$1,000.00000000	B-1	3.61500%
B-2	$0.00000000	$3.54291636	$0.00000000	$3.54291636	$1,000.00000000	B-2	3.86500%
B-3	$0.00000000	$4.91791636	$0.00000000	$4.91791636	$1,000.00000000	B-3	5.36500%
X	$0.00000000	$0.00000288	$0.00000000	$0.00000288	$969.18024484	R	1.93500%
R	$0.00000000	$0.00000000	$0.00000000	$0.00000000	$0.00000000	R-II	1.93500%
R-II	$0.00000000	$0.00000000	$0.00000000	$0.00000000	$0.00000000	LIBOR	1.61500%

Please contact the Bondholder Relations Department of U.S. Bank National Association at
(800) 934-6802 with any questions regarding this statement or your distribution.
U.S. BANK NATIONAL ASSOCIATION

Page 1

Credit Suisse First Boston Mortgage Securities Corp.
Home Equity Asset Trust Series 2004-4
Mortgage Pass-Through Certificates, HEAT Series 2004-4

STATEMENT TO CERTIFICATEHOLDERS
Section 4.04 of the PSA, dated June 1, 2004

Distribution Date:

27-Sep-04

		GROUP 1	GROUP 2	TOTAL
(i)	Principal Distributions:
	Beginning Balance	600,306,373.26	393,362,307.48	993,668,680.74
	Scheduled Principal	397,480.44	258,375.57	655,856.01
	Prepayments (Includes Curtailments)	7,362,371.86	6,821,529.80	14,183,901.66
	Net Liquidation Proceeds	0.00	0.00	0.00
	Loan Purchase Prices	0.00	0.00	0.00
	Total Principal Remittance	7,759,852.30	7,079,905.37	14,839,757.67
	Net Realized Losses	176,882.33	203,270.73	380,153.06
	Ending Balance	592,369,638.63	386,079,131.38	978,448,770.01
	Ending Count	4,349	2,046	6,395

(ii)

Aggregate Ending Collateral Balance

661,338,733.83

404,759,583.95

1,066,098,317.78

(iii)

Ending Overcollateralization Amount

2,361,837.21

(iv)	Prefunding Account:
	Beginning Balance	161,533,082.94	91,148,241.20	252,681,324.14
	Subsequent Transfer	92,456,378.11	72,437,127.54	164,893,505.65
	Added to available certificate principal	107,609.63	30,661.09	138,270.72
	Amount on Deposit in Prefunding Account	68,969,095.20	18,680,452.57	87,649,547.77
	*Ending Amounts in clude a Subsequent Transfer on 8/24/2004
(v)	Interest Distributions:
	Scheduled Interest - Net of Serv Fee & LPMI & Dividend Rewards	3,463,901.55	2,255,252.04	5,719,153.59
	Less Relief Act Interest Shortfall	0.00	0.00	0.00
	Less Net Prepayment Interest Shortfall	0.00	0.00	0.00
		3,463,901.55	2,255,252.04	5,719,153.59
(vi)	Capitalized Interest Account:
	Beginning Balance			1,055,797.84
	less: Capitalized Interest Requirement	237,045.19	64,209.48	301,254.67
	less: Withdrawal of Overfunded Interest Amount to Depositor			754,543.17
	Ending Balance			0.00

(vii)	Servicing Fee	97,013.65	63,877.19	160,890.84
	Trustee Fee	1,500.77	983.41	2,484.18
	Credit Risk Manager Fee	8,254.21	5,408.73	13,662.94
	Dividend Rewards	0.00	0.00	0.00
	Excess Servicing Fee	153,114.00	100,023.78	253,137.78
	FSA Premium	0.00	0.00	0.00

Page 2

Credit Suisse First Boston Mortgage Securities Corp.
Home Equity Asset Trust Series 2004-4
Mortgage Pass-Through Certificates, HEAT Series 2004-4

STATEMENT TO CERTIFICATEHOLDERS
Section 4.04 of the PSA, dated June 1, 2004

Distribution Date:

27-Sep-04

(viii)	Advances	Current Aggregate Advances as of determination date				1,434,865.16
		Outstanding Aggregate Advances as of end of prior calendar month				706,747.37

(ix)

Delinquency Information

	30-59 days delinquent		60-89 days delinquent		90 or more days delinquent
	Count	Balance	Count	Balance	Count	Balance
Group 1	94	11,200,762.95	5	645,717.36	1	129,674.41
Group 2	36	6,306,340.24	2	273,454.42	0	0.00
Total	130	17,507,103.19	7	919,171.78	1	129,674.41
*Note: The above statistics do not include loans in foreclosure or bankruptcy proceedings or REO properties.

	Outstanding Loans		Foreclosure		Bankruptcy		REO
	Count	Balance	Count	Balance	Count	Balance	Count	Balance	Market Value
Group 1	4,349	592,369,638.63	0	0.00	1	166,000.39	0	0.00	0.00
Group 2	2,046	386,079,131.38	0	0.00	1	51,950.45	0	0.00	0.00
Total	6,395	978,448,770.01	0	0.00	2	217,950.84	0	0.00	0.00

(x)	Number of Loans for which Prepayment Premiums were collected	62
	Principal Balance of Loans for which Prepayment Premiums were collected	10,036,361.90
	Current amount of Prepayment Premiums	287,178.65

(xi)	Current Delinquency Rate (60+days)					0.11883%
	Rolling Three Month Delinquency Rate (60+days)					0.04766%

(xii)	Number of Loans Repurchased					0
	Principal Balance of Loans Repurchased					0.00

(xiii)	Realized Losses incurred during the related Due Period					380,153.06
	Cumulative Realized Losses since Startup Day					380,153.06

(xiv)	Weighted Average Term to Maturity of Mortgage Loans	351
	Weighted Average Gross Coupon of Mortgage Loans	7.10202%
	Weighted Average Net Coupon of Mortgage Loans	6.58169%

Page 3

Credit Suisse First Boston Mortgage Securities Corp.
Home Equity Asset Trust Series 2004-4
Mortgage Pass-Through Certificates, HEAT Series 2004-4

STATEMENT TO CERTIFICATEHOLDERS
Section 4.04 of the PSA, dated June 1, 2004

Distribution Date:

27-Sep-04

(xv)

Aggregate number of Mortgage Loans in the pool

6,395

(xvi)

Insured Payment on Class A

0.00

(xvii)

Senior Enhancement Percentage

15.78211%

(xviii)

Net Excess Spread

2.40170%

(xix)	Deposit to Basis Risk Reserve Fund					0.00
	Basis Risk Reserve Fund Balance					5,000.00

(xx)	Interest Rate Cap Account
		Beginning Balance	125,000.00
		Deposits	100,145.83
		Withdrawals	225,145.83
		Ending Balance	0.00

Target Amount for the preceding Distribution Date

22,395,189.06

(xxi)

Designated Mortgage Loans transferred

2297

(xxii)

Designated Mortgage Loans remaining to be transferred

Page 4

Credit Suisse First Boston Mortgage Securities Corp. Home Equity Asset Trust 2004-4. 8-K