No. J1644 is a HCPCS Level II code, maintained by CMS, that identifies the drug supplied. CPT codes are five-digit numbers from the AMA that describe services. Giving the drug, for example an injection or infusion, is usually reported with a separate CPT administration code.

What is the Medicare payment limit for J1644?

$0.201 per 1000 units, effective October 1, 2026 through December 31, 2026, from CMS's Part B drug payment limit file. Multiply by the units billed for the allowed amount before deductible and coinsurance. It is not a coverage decision.

What is one billing unit of J1644?

One unit of J1644 is 1000 units, as stated in the code's descriptor. Units to report = dose given ÷ 1000 units.

J1644 J-Code: Heparin sodium — Billing Units & NDCs

In short

J1644 is the HCPCS Level II code for injection, heparin sodium, per 1000 units. CMS assigns NDCs for Heparin (Porcine) In D5W, Heparin (Porcine) In Nacl, Heparin Sodium and Heparin Sodium (Porcine) and 1 more to it. One billing unit is 1000 units. The Medicare Part B payment limit is $0.201 per unit (October 1, 2026 through December 31, 2026).

Code

CMS HCPCS file

HCPCS codeJ1644

Billing unit1000 units

Descriptor: Injection, heparin sodium, per 1000 units
Short descriptor: Inj heparin sodium per 1000u
Code set: HCPCS Level II, maintained by CMS
Effective: Jan 1, 2003

The billing unit is read from the descriptor. Confirm it against the CMS file before billing.

Medicare Part B payment limit

CMS ASP file

Payment limit per unit$0.201

Per1000 units

Coinsurance20%

Effective October 1, 2026 through December 31, 2026. Payment allowance limits subject to the ASP methodology are based on 2Q26 ASP data. A payment limit is not a coverage decision; the Medicare contractor decides coverage. CMS ASP pricing files

Units and claim line

Units = dose given ÷ 1000 units. For example, 100000 units is 100 units. Enter the dose to get the units and the NDC line for the CMS-1500 and the 837P.

Dose given (units)

HCPCS units (1 unit = 1,000 units)

Modifier

NDC (11-digit)

NDC unit qualifier

NDC quantity

Enter the dose given to build the claim line.

NDCs billed under J1644

CMS’s ASP NDC–HCPCS crosswalk (effective October 1, 2026 through December 31, 2026) assigns 138 NDCs to J1644 for Heparin (Porcine) In D5W, Heparin (Porcine) In Nacl, Heparin Sodium, Heparin Sodium (Porcine) and Heparin Sodium in NaCl. Billing units per package are CMS’s figures for this code’s unit.

NDCs assigned to J1644 in the CMS ASP crosswalk
Drug	NDC (11-digit)	Labeler	Package	Billing units per package
Heparin (Porcine) In D5W	00264-9567-10	B. Braun Medical Inc.	24 × 500	480
Heparin (Porcine) In D5W	00264-9577-10	B. Braun Medical Inc.	24 × 500	600
Heparin (Porcine) In D5W	00264-9587-20	B. Braun Medical Inc.	24 × 250	600
Heparin (Porcine) In D5W	63323-0522-77	FreseniUS Kabi USA, LLC	24 × 500	600
Heparin (Porcine) In D5W	63323-0523-74	FreseniUS Kabi USA, LLC	24 × 250	600
Heparin (Porcine) In Nacl	00264-9872-10	B. Braun Medical Inc.	24 × 500	24
Heparin (Porcine) In Nacl	00338-0433-04	Baxter Healthcare Corporation	12 × 1,000	24
Heparin (Porcine) In Nacl	00409-7620-03	Pfizer Inc	18 × 500	18
Heparin (Porcine) In Nacl	00409-7650-62	Pfizer Inc	24 × 250	600
Heparin (Porcine) In Nacl	63323-0517-74	FreseniUS Kabi USA, LLC	24 × 250	600
Heparin (Porcine) In Nacl	63323-0518-77	FreseniUS Kabi USA, LLC	24 × 500	600
Heparin (Porcine) In NaCl	00338-0424-18	Baxter Healthcare Corporation	18 × 500	18
Heparin Sodium	00264-9872-00	B. Braun Medical Inc.	12 × 1,000	24
Heparin Sodium	00338-0431-03	Baxter Healthcare Corporation	18 × 500	18
Heparin Sodium	00404-9872-01	Henry Schein Inc.	1	5
Heparin Sodium	00404-9873-01	Henry Schein Inc.	1	10
Heparin Sodium	00404-9979-01	Henry Schein Inc.	1	1
Heparin Sodium	00409-1402-12	Pfizer Inc	50 × 1	250
Heparin Sodium	00409-4520-30	Pfizer Inc	30 × 250	750
Heparin Sodium	00781-3538-25	Sandoz Inc.	25 × 1	25
Heparin Sodium	00781-3540-25	Sandoz Inc.	25 × 10	250
Heparin Sodium	00781-3543-25	Sandoz Inc.	25 × 30	750
Heparin Sodium	00781-3545-25	Sandoz Inc.	25 × 1	125
Heparin Sodium	00781-3550-25	Sandoz Inc.	25 × 10	1,250
Heparin Sodium	00781-3555-25	Sandoz Inc.	25 × 2	50
Heparin Sodium	25021-0400-66	Sagent Pharmaceuticals	25 × 1	25
Heparin Sodium	25021-0400-67	Sagent Pharmaceuticals	25 × 10	250
Heparin Sodium	25021-0400-68	Sagent Pharmaceuticals	25 × 30	750
Heparin Sodium	25021-0402-66	Sagent Pharmaceuticals	25 × 1	125
Heparin Sodium	25021-0403-66	Sagent Pharmaceuticals	25 × 1	250
Heparin Sodium	51662-1409-01	HF Acquisition Co. LLC, DBA HealthFirst	5	50
Heparin Sodium	51662-1409-03	HF Acquisition Co. LLC, DBA HealthFirst	25 × 5	1,250
Heparin Sodium	51662-1434-01	HF Acquisition Co. LLC, DBA HealthFirst	1	10
Heparin Sodium	51662-1486-01	HF Acquisition Co. LLC, DBA HealthFirst	1	10
Heparin Sodium	63323-0542-13	FreseniUS Kabi USA, LLC	25 × 1	250
Heparin Sodium	63323-0542-14	FreseniUS Kabi USA, LLC	25 × 5	1,250
Heparin Sodium	63323-0543-13	FreseniUS Kabi USA, LLC	25 × 0.5	125
Heparin Sodium	71288-0405-81	Meitheal Pharmaceuticals Inc.	24 × 0.5	120
Heparin Sodium	71288-0406-82	Meitheal Pharmaceuticals Inc.	24 × 1	120
Heparin Sodium	71288-0449-02	Meitheal Pharmaceuticals Inc.	25 × 1	25
Heparin Sodium	71288-0450-02	Meitheal Pharmaceuticals Inc.	25 × 1	125
Heparin Sodium	71288-0451-02	Meitheal Pharmaceuticals Inc.	25 × 1	250
Heparin Sodium	71839-0117-25	BE Pharmaceuticals Inc.	25 × 2	50
Heparin Sodium	71839-0118-25	BE Pharmaceuticals Inc.	25 × 0.5	125
Heparin Sodium	72603-0179-25	Northstar RxLLC	25 × 10	250
Heparin Sodium	72603-0214-25	Northstar RxLLC	25 × 10	1,250
Heparin Sodium	72603-0224-25	Northstar RxLLC	25 × 1	500
Heparin Sodium	72603-0234-25	Northstar RxLLC	25 × 1	25
Heparin Sodium	72603-0250-25	Northstar RxLLC	25 × 1	25
Heparin Sodium	72603-0267-25	Northstar RxLLC	25 × 30	750
Heparin Sodium	72603-0336-25	Northstar RxLLC	25 × 2	50
Heparin Sodium	72603-0412-25	Northstar RxLLC	25 × 1	125
Heparin Sodium	72603-0456-25	Northstar RxLLC	25 × 1	125
Heparin Sodium	72603-0501-25	Northstar RxLLC	25 × 1	250
Heparin Sodium	72603-0579-25	Northstar RxLLC	25 × 1	250
Heparin Sodium	81565-0203-02	Phlow Corporation	25 × 10	250
Heparin Sodium	81952-0112-06	Hepalink USA, Inc.	25 × 1	25
Heparin Sodium	81952-0112-09	Hepalink USA, Inc.	25 × 10	250
Heparin Sodium	81952-0112-10	Hepalink USA, Inc.	25 × 30	750
Heparin Sodium	81952-0113-06	Hepalink USA, Inc.	25 × 1	250

Showing 60 of 138. The full list is in the CMS crosswalk file.

J1644: common questions

Is J1644 a CPT code?: No. J1644 is a HCPCS Level II code, maintained by CMS, that identifies the drug supplied. CPT codes are five-digit numbers from the AMA that describe services. Giving the drug, for example an injection or infusion, is usually reported with a separate CPT administration code. CPT codes for drug administration.
What NDCs are billed under J1644?: CMS's ASP crosswalk for October 1, 2026 through December 31, 2026 lists 138 NDCs under J1644, for Heparin (Porcine) In D5W, Heparin (Porcine) In Nacl, Heparin Sodium, Heparin Sodium (Porcine) and Heparin Sodium in NaCl. The table on this page shows each one with its billing units per package.
What is the Medicare payment limit for J1644?: $0.201 per 1000 units, effective October 1, 2026 through December 31, 2026, from CMS's Part B drug payment limit file. Multiply by the units billed for the allowed amount before deductible and coinsurance. It is not a coverage decision.
What is one billing unit of J1644?: One unit of J1644 is 1000 units, as stated in the code's descriptor. Units to report = dose given ÷ 1000 units. J-code billing units.

J1644 — Injection, heparin sodium, per 1000 units