HTS heading 3507 · Chapter 35
HTS 3507: Enzymes
HTS heading 3507 covers enzymes; prepared enzymes not elsewhere specified or included. It has 5 tariff lines with a duty rate; the general (MFN) rates are Free (4 lines), 3.25% (1 line).
Imports may also owe Chapter 99 tariffs (Section 232, 301 or 201) depending on origin and date, plus the Merchandise Processing Fee and, by sea, the Harbor Maintenance Fee.
Rates from the 2026 HTS Revision 22, effective October 30, 2026. Source: U.S. International Trade Commission.
Tariff lines and duty rates
| HTS code | Description | General | Special | Column 2 | Estimate |
|---|---|---|---|---|---|
| 3507.10.00.00 | Rennet and concentrates thereof[kg] | Free | Free | Estimate → | |
| 3507.90 | Other: | ||||
| 3507.90.20.00 | Pencillin G amidase[kg] | Free | 25% | Estimate → | |
| 3507.90.70 | Other | Free | 25% | ||
| 3507.90.70.10 | Enzymes – proteases, amylases, lipases, cellulases, pectinases, oxidases, and catalases[kg] | Estimate → | |||
| 3507.90.70.80 | Other[kg] | Estimate → | |||
| 3601.00.00.00 | Propellant powders[kg] | 3.25% | Free (A,AU,BH,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG) | 60% | Estimate → |
| 3602.00.00 | Prepared explosives, other than propellant powders | Free | Free | ||
| 3602.00.00.30 | Dynamite and other high explosives, put up in cartridges, sticks or other forms, suitable for blasting[kg] | Estimate → | |||
| 3602.00.00.60 | Other[kg] | Estimate → |
9 lines shown. Statistical suffixes (the last two digits) inherit the rate of the 8-digit subheading above them.
Example: base duty and fees on $10000
For HTS 3601.00.00.00 at the general rate of 3.25%, shipped by ocean, before any Chapter 99 tariffs:
| Base duty (3.25%) | $325.00 |
| Merchandise Processing Fee (0.3464%, min $34.58) | $34.64 |
| Harbor Maintenance Fee (0.125%) | $12.50 |
| Duty and fees | $372.14 |
Origin-specific tariffs can multiply this. Run this example from China or from Mexico to see every line.
Special program codes in this heading
- A, A*, A+
- Generalized System of Preferences (GSP)
- AU
- U.S.–Australia FTA
- BH
- U.S.–Bahrain FTA
- CL
- U.S.–Chile FTA
- CO
- U.S.–Colombia Trade Promotion Agreement
- D
- African Growth and Opportunity Act (AGOA)
- E, E*
- Caribbean Basin Economic Recovery Act
- IL
- U.S.–Israel FTA
- JO
- U.S.–Jordan FTA
- KR
- U.S.–Korea FTA (KORUS)
- MA
- U.S.–Morocco FTA
- OM
- U.S.–Oman FTA
- P, P+
- CAFTA-DR
- PA
- U.S.–Panama Trade Promotion Agreement
- PE
- U.S.–Peru Trade Promotion Agreement
- S, S+
- USMCA (United States–Mexico–Canada Agreement)
- SG
- U.S.–Singapore FTA
A special rate applies only when the goods qualify under that program's rules of origin and the claim is made at entry.