One Week Into the 12.5% Section 301 Tariff: How Specific-Duty Items Are Calculated, and Where the “15% Cap” Stands

Updated July 29, 2026

It has been about a week since the new Section 301 tariff took effect on July 24, 2026, bringing the total duty on most Japanese goods to 12.5% (combined with existing MFN rates).

The launch itself was widely covered. What has become clearer over the past week are the practical details — the points that actually determine what importers and exporters of Japanese food will pay. This follow-up covers the three developments that matter most, based on JETRO’s July 27 briefing materials and official statements from both governments.

The conversion rule for specific-duty and compound-duty items has been clarified
Both governments have confirmed that the 15% cap under the 2025 U.S.–Japan agreement still stands
Refunds of suspended IEEPA reciprocal tariffs are moving

The Basics, Restated: 12.5% Is a Ceiling, Not a Surcharge

First, a quick refresher, because this is still the most misunderstood point.

The Section 301 tariff does not add a flat 12.5% on top of everything. Instead:

If the MFN (general) rate is below 12.5%: the Section 301 duty tops it up so the combined rate equals 12.5%
If the MFN rate is 12.5% or higher: the Section 301 duty is zero — the item pays MFN only, effectively unchanged

In other words, the products hit hardest are the ones that used to enter duty-free or at low rates. Many processed Japanese foods — soy sauce, miso, confectionery — fall into this “low MFN, bigger increase” group.

Meanwhile, certain agricultural products are on the exclusion list, including tea (HTS heading 0902, which covers matcha). Checking your HTS codes against the Federal Register annex is step one for every product line.

How Specific-Duty and Compound-Duty Items Are Calculated

This is the most practically important clarification of the week.

Many food HTS codes carry a specific duty (e.g., “X cents per kilogram”) or a compound duty (a percentage plus a per-unit amount). Since the 12.5% threshold is expressed as a percentage, it was initially unclear how these items would be evaluated.

JETRO’s July 27 materials lay out the method: take the duty amount payable under the MFN rate, divide it by the customs value of the goods, and use the resulting percentage as the ad valorem equivalent.

Example

MFN rate: 50 cents/kg (specific duty)
Customs value: $10.00/kg

Ad valorem equivalent: $0.50 ÷ $10.00 = 5%

Since 5% is below 12.5%, this item would owe an additional 7.5% in Section 301 duty, for a combined 12.5%.

The critical implication: the ad valorem equivalent depends on your unit price. Under the same HTS code, a higher-priced product has a lower ad valorem equivalent — and therefore a larger Section 301 top-up. A lower-priced product may convert to a rate above 12.5% and owe no Section 301 duty at all.

For specific-duty items, there is no way to know your real exposure without running the numbers on your actual invoice prices. Do the calculation yourself before your customs broker does it for you — and make sure you agree on the method.

Is the 15% Cap From the U.S.–Japan Agreement Still Alive?

The other major question: how does this tariff interact with the July 2025 U.S.–Japan agreement, which capped reciprocal tariffs on Japanese goods at 15%?

Both sides have now spoken.

U.S. side: USTR Ambassador Greer said in a June 4 media interview that the U.S. would honor the tariff-rate ceilings in its agreements with the EU, Japan, and other partners.
Japan side: METI Minister Akazawa said at his July 24 press conference that both governments share the understanding that last year’s agreement remains unchanged, and that Japan has confirmed with the U.S. that no additional tariffs exceeding the agreement will ultimately be imposed on Japan.

At 12.5%, the current rate sits below the 15% ceiling, and both governments treat it as within the framework. That said, Section 301 actions can be modified and product lists can change. The realistic posture: treat 15% as the hard ceiling in your planning, and monitor USTR and Federal Register notices quarterly.

Money Coming Back: IEEPA Reciprocal Tariff Refunds

One more item that should not fall off your radar: refunds.

The IEEPA-based reciprocal tariffs were suspended on February 24, 2026, following the Supreme Court’s ruling. Importers who paid reciprocal tariffs between August 2025 and February 2026 may be entitled to refunds.

The route depends on the status of the entry:

Before liquidation: file a Post Summary Correction (PSC)
After liquidation: file a protest (CBP Form 19) within 180 days of liquidation

If you are the importer of record, check your entries now. If your U.S. importer is a separate party, confirm that they are pursuing the refunds — even a few percentage points across six months of import volume adds up to real money.

This Week’s Checklist

For anyone importing Japanese food into the U.S. — or exporting to a U.S. buyer — here is what to verify this week:

HTS codes: cross-check every product against the exclusion list in the Federal Register annex
MFN rates: for ad valorem items, compare against 12.5%; for specific/compound duties, convert using your actual invoice unit prices
Landed cost: rerun FOB-to-landed calculations with the Section 301 duty included, and model the impact on wholesale and retail pricing
Broker alignment: share your ad valorem conversion math with your customs broker so entries are filed consistently
IEEPA refunds: confirm PSC or protest status for reciprocal tariffs paid from August 2025 through February 2026
Contracts: if you sell or buy on DDP terms, revisit who bears the tariff under your current agreements

Need Help With Tariffs, FSVP, or FDA Compliance?

Studio 1414 supports U.S. importers and Japanese exporters end to end — HTS-level tariff analysis, FSVP agent services, FDA registration, and import logistics for Japanese food products. If the new tariff has raised questions about your specific product line, we are happy to walk through the numbers with you.

Sources: JETRO, “Overview of the Section 301 Tariff Concerning Forced Labor” (as of July 27, 2026); USTR Federal Register notices and fact sheets; METI Minister Akazawa’s press conference (July 24, 2026)