The 100% Pharma Tariff Isn't 100% for Everyone

On September 29, the next phase of the U.S. Section 232 drug tariff takes effect. The headline is 100%, but the rate that actually applies to your shipment could be 15%, 0%, or something else entirely. Knowing which lane you're in is the whole job.

On September 29, 2026, the U.S. Section 232 tariff on patented pharmaceuticals reaches nearly every remaining importer. The 17 largest drugmakers, listed in Annex III, were hit first, on July 31. But treating this simply as "a 100% tariff on pharmaceuticals" misses the point that matters commercially: the same molecule can enter at 100%, 15%, or 0% depending on its origin, its maker, and the agreements behind it. Before your next entry, the question is not whether the tariff exists. It is which lane your product is in.

What the measure is

The tariff comes from Presidential Proclamation 11020, signed April 2, 2026 under Section 232 of the Trade Expansion Act of 1962, the same national-security statute used for steel and aluminum, and published in the Federal Register on April 9. It sets a default 100% ad valorem duty on covered patented pharmaceutical products and associated active ingredients (APIs), subject to a set of lower-rate and zero-rate pathways. The stated basis is national security: Commerce found the U.S. dangerously reliant on imported patented drugs, with roughly 53% of patented pharmaceuticals sold in the U.S. made abroad. The goal is to force production onshore.

There are two effective dates: July 31, 2026 for the Annex III companies, and September 29, 2026 for everyone else.

The lanes that decide what you actually pay

CBP implements this through separate Chapter 99 provisions, and the rate swings enormously by lane:

100% (HTS 9903.04.60): the default for covered patented products with no qualifying agreement, trade-deal origin, or exemption. 15% (9903.04.62): covered products of the European Union, Japan, South Korea, Switzerland, and Liechtenstein, reflecting pharmaceutical commitments in existing trade deals. This is the lane that matters most, because it captures a large share of U.S. drug imports, and it is the one a "100% tariff" headline hides. 10% (9903.04.63): covered products of the United Kingdom, under the proclamation. The U.S.-UK pharmaceutical pricing arrangement provides a pathway to 0%, and some sources already report UK products at 0%. CBP's own Chapter 99 code still reads 10%, so confirm the current UK treatment at entry rather than assuming either figure. 20% (9903.04.64): companies with a Commerce-approved onshoring plan but no pricing deal. This rate rises to 100% on April 2, 2030. 0% (9903.04.65 to .69): companies with both an approved onshoring plan and a signed MFN pricing agreement (through January 20, 2029); generics and their ingredients; U.S.-origin products; certain dosage-form products made with U.S.-origin APIs; Annex II companies; and the specific exempt categories.

One mechanical rule ties it together. For the 100%, 20%, and 15% lanes, the Section 232 rate is all-inclusive: it replaces the ordinary MFN base duty rather than stacking on top of it. If your MFN rate is 5% and your Section 232 rate is 15%, you pay 15%, not 20%. If the MFN rate is higher than the Section 232 rate, you pay the MFN rate.

What's exempt, and what's only exempt for now

Generic pharmaceuticals and biosimilars are not subject to the Section 232 tariff at this time, and Commerce must report within one year on whether to act on generics. Be careful with the framing here: that is a current exemption pending review, not a guaranteed multi-year one. A separate July 22, 2026 announcement floated a future generic tariff, but it was made outside a proclamation and is not, on its own, binding legal action.

Also carved out at 0% are specified orphan drugs, nuclear medicines, plasma-derived therapies, fertility treatments, cell and gene therapies, antibody-drug conjugates, certain CBRN medical countermeasures, and animal-health products, each subject to the proclamation's conditions.

Don't reduce the coverage test to an Orange Book lookup

It is tempting to decide scope by checking whether a drug carries an unexpired U.S. patent in the FDA's Orange Book. Patent status does inform whether a product is "patented." But the customs determination is made through the HTSUS, the Chapter 99 provisions, and U.S. Note 40, with CBP identifying the relevant Chapter 29 and 30 classifications. Decide from the actual tariff provisions and product facts, not from a shortcut.

September 29 is a real date, and it's the entry that counts

CBP told importers that, from July 31, entries in the relevant Chapter 29 and 30 classifications must report the applicable Chapter 99 provision, and that non-Annex-III products could use a 0% interim provision (9903.04.61) through September 28. From September 29, the actual rate applies by product, origin, company, and agreement. The trigger is the date a product is entered for consumption or withdrawn from warehouse for consumption, not the sailing date. A covered product that ships from Asia in late August can land right on the deadline.

What importers should do now Classify first, then price. Start with the exact HTSUS classification and the applicable Chapter 99 provision, not with an assumed rate. Pin down origin. EU, Japan, Korea, Switzerland, or Liechtenstein origin can mean 15% where another origin means 100%. UK origin means 10% under the code, with a possible 0% you should confirm. Verify company status in writing. Onshoring plan, MFN pricing deal, Annex II or III listing: each changes the lane, and none should be assumed. Separate patented from generic and exempt. The regime does not treat every pharmaceutical the same way, so sort your portfolio before entry. Review entries around September 29 by clearance date, not sailing date. For in-transit cargo, know your projected entry date.

September 29 is not the day pharmaceuticals "become subject to a 100% tariff." It is the day the interim zero-rate treatment ends for most remaining companies and the full Section 232 rate matrix goes live. For some importers the rate is 100%. For many it is 15% or 0%. The costly mistake is not failing to prepare for 100%. It is assuming you know your rate before you have confirmed which Chapter 99 provision your product actually falls under.

This article is informational and is not legal, customs, tax, or medical advice. Section 232 treatment depends on classification, origin, company status, applicable agreements, and current CBP guidance, which can change. Confirm your treatment with a licensed customs broker or trade counsel before entry.

Source:

Federal Register / Casa Blanca (primaria) — Proclamación 11020, "Adjusting Imports of Pharmaceuticals..." (pub. 9 abr. 2026): 100% default, fechas 31 jul. y 29 sep. 2026, genéricos exentos por ahora: https://www.federalregister.gov/documents/2026/04/09/2026-06956/adjusting-imports-of-pharmaceuticals-and-pharmaceutical-ingredients-into-the-united-states CBP (vía C.H. Robinson) (operativa) — provisiones capítulo 99: 100% (.60), 15% UE/Japón/Corea/Suiza/Liechtenstein (.62), 10% RU (.63), 20% onshoring (.64), 0% (.65–.69), interina (.61): https://www.chrobinson.com/en-us/resources/insights-and-advisories/client-advisories/2026q3/07-31-26-cbp-implements-section-232-tariffs-on-patented-pharmaceuticals/ Thompson Hine (secundaria) — 15% para UE/Liechtenstein/Japón/Corea/Suiza y 10% RU "consistente con acuerdos comerciales existentes"; mecánica de tasa: https://www.thompsonhinesmartrade.com/2026/04/president-trump-announces-section-232-tariffs-on-pharmaceuticals-and-active-pharmaceutical-ingredients/ Carra Globe (secundaria) — tratamiento all-inclusive (232 reemplaza MFN base, no apila); guía antes del 29 sep.: https://carraglobe.com/section-232-pharmaceutical-tariffs-2026/ Mohawk Global / pharmanow (secundarias; conflicto sobre RU 0% vs 10%) — Mohawk reporta RU a 0%; pharmanow lo mantiene en "10%, puede bajar a 0%": https://mohawkglobal.com/word-from-the-white-house/section-232-tariffs-on-patented-pharmaceutical-imports-take-effect/