9903.03.13 Explained: Canada Dairy Tariff, 50% Rate, and Scope

Status as of October 5, 2026. The September 8, 2026 proclamations left this list unchanged, and since September 15, 2026 the dairy heading is the only Section 338 heading that still carries the Section 232 exception (9903.03.15). Since September 29, 2026 a set of the listed products (certain whey, sugar syrup and molasses lines and non-alcoholic beer) is excluded from importation into the United States altogether; goods imported but not entered before that date remain at the 50 percent duty. CBP guidance: CSMS # 69851916.

Key Points

• 9903.03.13 adds a 50 percent ad valorem duty on products of Canada enumerated in U.S. note 51(b)(2), covering a dairy action under the Section 338 Canada program.
• The rate took effect August 22, 2026, not August 19, 2026 as previously stated; entries dated on or after August 22, 2026 for covered Canadian goods must carry this code.
• No end date has been announced as of October 2, 2026; the 50 percent rate continues until further notice.
• The product list spans 52 HTS lines, concentrated in Chapters 04 (dairy) and 17 (sugars), plus selected lines in Chapters 05, 12, and 13.
• The 50 percent additional duty stacks on top of the regular column 1 rate for each underlying HTS line; it does not replace it.

On this page

1. What changed and when
2. Legal authority and program background
3. Rate and effective window
4. Country scope
5. Product scope: what is on the U.S. note 51(b)(2) list
6. How 9903.03.13 stacks with other duties
7. How to report this code on an entry
8. Required actions for importers and brokers
9. Key references

HTS code 9903.03.13 is a Chapter 99 overlay that imposes a 50 percent additional ad valorem duty on products of Canada enumerated in U.S. note 51(b)(2), covering a specific dairy action under the Section 338 Canada program. The official heading text reads: Products of Canada enumerated in U.S. note 51(b)(2) (dairy action): +50% ad valorem. The rate became effective August 22, 2026 and has no announced end date as of October 2, 2026. The links in this article go to the primary documents: the proclamations, Federal Register notices, and official tariff schedule pages themselves. Read the source.

What changed and when

The HTSUS provision text for 9903.03.13 was re-issued after this article was first published on August 4, 2026. Two facts changed materially. First, the effective date moved from August 19, 2026 (as stated in the original article) to August 22, 2026. Second, the official heading text was confirmed in its current form. Every rate, window, and scope statement in this article now reflects those re-issued facts as of October 2, 2026. If you relied on August 19 as your trigger date, review any entries filed between August 19 and August 21, 2026 with your broker.

Legal authority and program background

This code was created under the Section 338 Canada program. The governing legal authority is Proclamation 11047, published at 91 FR 46653 (Federal Register document 2026-14992). The product scope and country applicability are defined in U.S. note 51 to Chapter 99 of the Harmonized Tariff Schedule of the United States, specifically U.S. note 51(b)(2), which the code's official heading references directly.

9903.03.13 is one of several Section 338 Canada codes. These codes are entirely separate from any earlier Chapter 99 programs and must not be confused with them. Always verify the specific note and subparagraph when classifying an entry.

You can review the official Federal Register notice at federalregister.gov (FR doc 2026-14992, 91 FR 46653) and the current HTSUS text at hts.usitc.gov.

Rate and effective window

The additional duty rate under 9903.03.13 is 50 percent ad valorem, applying to the dutiable value of the imported goods. Key timing facts:

• Effective date: August 22, 2026. Only entries made on or after that date are subject to this duty.
• End date: No announced end date as of October 2, 2026. The 50 percent rate continues until further notice or a subsequent proclamation.
• Entries before August 22, 2026 are not covered by this code, regardless of when goods were ordered or shipped.

Because no sunset date has been announced, importers should not plan around an automatic expiration. Confirm the current status in the 2026 tariff code overview or check the current HTSUS at hts.usitc.gov for any modifications.

Country scope

This code applies exclusively to products of Canada. Country of origin, not country of export or country of shipment, determines whether goods fall within scope. Goods originating in any country other than Canada are not subject to 9903.03.13, even if they transit through Canada. If your supply chain involves Canadian processing of third-country inputs, confirm the country-of-origin determination with your broker before filing any entry under this code.

Product scope: what is on the U.S. note 51(b)(2) list

The goods covered are those enumerated in U.S. note 51(b)(2), which the facts identify as a dairy action. The product list is large, covering 52 HTS lines in total. The first 40 lines confirmed in the facts span primarily Chapters 04 and 17 of the regular tariff schedule, with additional lines in Chapters 05, 12, and 13, effective August 22, 2026 onward:

Chapter 04: dairy, eggs, and related products

• 0402.10.05, 0402.10.10, 0402.10.50: Milk and cream in powder, granules, or other solid forms, not containing added sugar or sweetening matter
• 0402.21.02 through 0402.21.90: Milk and cream in solid form, containing added sugar or sweetening matter
• 0402.91.03, 0402.91.06: Milk and cream, not in solid form, not containing added sugar (selected subheadings)
• 0402.99.68: Other milk and cream preparations
• 0404.10.05 through 0404.10.90: Whey and modified whey products
• 0404.90.10 through 0404.90.70: Other dairy products of heading 0404

Chapter 05 and other agricultural chapters

• 0506.90.00: Bones and horn-cores not elsewhere specified (ossein and bones treated with acid)
• 1210.20.00: Hop cones, ground, powdered, or in pellets; lupulin
• 1301.90.91: Lac and natural gums, resins, and other vegetable saps and extracts

Chapter 17: sugars and sugar confectionery

• 1702.11.00, 1702.19.00: Lactose and lactose syrup
• 1702.30.28, 1702.40.28, 1702.60.28: Glucose and fructose syrups (selected subheadings)
• 1702.90.35, 1702.90.58, 1702.90.68: Other sugars and sugar syrups
• 1703.10.30: Cane molasses

This list represents only the first 40 of 52 total lines enumerated in U.S. note 51(b)(2). Confirm the complete list in the current HTSUS at hts.usitc.gov or with your broker to ensure no covered lines are missed.

How 9903.03.13 stacks with other duties

Chapter 99 overlay codes like 9903.03.13 are additional duties. They do not replace the regular column 1 general rate that applies to the underlying Chapter 04 or Chapter 17 classification. An entry line for a covered Canadian dairy product will carry both:

• The regular HTS rate from the Chapter 1-97 classification line, which may itself include specific rates, tariff-rate quota rates, or other duties depending on the product
• The 50 percent additional duty from 9903.03.13, effective August 22, 2026 onward

Other Chapter 99 codes from separate programs may also stack on the same entry line if their own scope conditions are met. The facts block does not specify interaction rules beyond the 50 percent additional rate, so confirm full stacking with your broker using the current HTSUS and any applicable CBP guidance. Use the duty calculator to estimate your combined duty exposure before filing.

For entries involving classification questions or underpayment risk, see our overview of 19 USC 1592(d) duty demand authority, which explains how CBP can collect unpaid duties separate from a penalty action.

How to report this code on an entry

Chapter 99 codes ride alongside the regular Chapter 1-97 classification. On a CBP entry, the importer of record or broker will report:

1. The regular HTS line (for example, 0402.10.05 for a specific powdered milk product), with the standard column 1 duty rate
2. 9903.03.13 as a secondary classification line on the same entry, capturing the 50 percent additional duty
3. Canada as the country of origin, which triggers applicability

Entries dated before August 22, 2026 must not carry this code. Entries on or after August 22, 2026 for covered Canadian goods must include it. An omission on a post-effective-date entry will result in underpayment of duties, which CBP can pursue through formal demand or liquidation adjustment. For guidance on document retention obligations, see our article on customs recordkeeping requirements and the five-year rule.

Required actions for importers and brokers

• Audit your Canadian dairy supply chain. Cross-reference every HTS line you import from Canada against the full U.S. note 51(b)(2) list in the current HTSUS to identify which of your products are in scope. All 52 covered lines are active as of August 22, 2026.
• Review any entries filed between August 19 and August 21, 2026. The effective date in the original article was wrong; the correct date is August 22, 2026. If you applied 9903.03.13 to entries on August 19-21, confirm with your broker whether a correction is needed.
• Update your entry instructions and ACE filing templates. Instruct your broker to add 9903.03.13 as a secondary line on all covered entries dated on or after August 22, 2026. Do not apply it to earlier entries.
• Recalculate landed costs. A 50 percent additional ad valorem duty materially changes the economics of Canadian dairy sourcing. Update pricing models, purchase orders, and supplier agreements accordingly.
• Monitor the Federal Register and HTSUS for changes. No end date has been announced as of October 2, 2026. Watch for any proclamation modifying or terminating Proclamation 11047 or U.S. note 51, and confirm the current rate window with your broker before each shipment.

Key references

• Federal Register document 2026-14992, 91 FR 46653: Proclamation 11047, the legal authority establishing 9903.03.13 and the Section 338 Canada dairy action
• HTSUS, hts.usitc.gov: Official harmonized tariff schedule, including Chapter 99, U.S. note 51, and the full 52-line product list under note 51(b)(2)
• CBP.gov: CBP guidance, CSMS messages, and entry filing instructions
• federalregister.gov: Federal Register search for subsequent proclamations or modifications affecting Proclamation 11047
• 2026 tariff code overview: CustomsGenius summary of active Chapter 99 codes for 2026
• Duty calculator: Estimate combined duty exposure including the 50 percent 9903.03.13 overlay