What moved, when it was published, and when it took force
8 entries, newest first, each with two dates and its primary source. Checked 11 October 2026.
One entry per change that a seller into Mexico needs to know: the date it was published, the date it took force, the primary source, the industries and the Book 1 products it touches. Newest first. Every entry was checked against its primary source on 11 October 2026; where a detail comes from another official text, the entry names it.
US replaces struck-down tariffs with a 10 percent Section 301 duty
After the US Supreme Court ruled on 20 February 2026 that the emergency-powers law does not authorise tariffs, a temporary Section 122 surcharge ran until 24 July 2026, and a Section 301 duty of 10 percent on goods of Mexico applied from that day. US Customs said it does not apply to goods entered duty-free under the USMCA (CBP message 69326983, 23 July 2026). It touches goods Mexico sells to the US, not goods sold into Mexico.
Source: Federal Register, 91 FR 47318, document 2026-15181 (USTR). Industries: Exporters from Mexico to the United States. Book 2 reference: Chapter 3. Checked 11 October 2026.
USMCA first joint review: no extension, annual reviews begin
At the six-year joint review the United States did not agree to renew the agreement in its current form. Under the agreement's review clause (Article 34.7) that starts annual joint reviews; the agreement stays in force, with its term running to 1 July 2036 unless the three parties confirm an extension.
Source: Office of the US Trade Representative, statement on the USMCA joint review. Industries: All industries. Book 2 products: all fifteen. Book 2 reference: Chapter 3. Checked 11 October 2026.
New label standard for medical devices published
NOM-137-SSA1-2025 sets the health-information label for medical devices for human use, including traceability. It replaces NOM-137-SSA1-2008 when it enters into force, 360 calendar days after publication, with 180 more days to use up existing packaging.
Source: Diario Oficial de la Federación, via SIDOF (Secretaría de Gobernación). Industries: Dental and medical, Health, pharmacy and OTC. Book 2 products: Dental equipment and supplies. Book 2 reference: Chapter 11. Checked 11 October 2026.
Decree adds 185 tariff lines; bicycles rise to 35 percent
A presidential decree set duties of 5 to 35 percent on 185 more tariff lines for goods without a trade agreement, including bicycles without a motor (8712.00.05) and their frames and forks at 35 percent, and adjusted the PROSEC sector programmes.
Source: Diario Oficial de la Federación (evening edition), as published by the Cámara de Diputados. Industries: Sports, outdoor and cycling, Building, electrical and lighting, Manufacturing and machinery. Book 2 products: British folding bicycles, Electrical fixtures. Book 2 reference: Chapter 12. Checked 11 October 2026.
Health law reform: registrations extendable for ten years
A reform of the Ley General de Salud keeps the five-year sanitary registration for medicines and medical devices but allows extensions for ten-year terms on request; missing the extension deadline, or changing the product or raw-material maker without approval, cancels it. A new article 262 Bis places registered medical devices under incident monitoring (tecnovigilancia).
Source: Ley General de Salud, consolidated text, Cámara de Diputados. Industries: Health, pharmacy and OTC, Dental and medical. Book 2 products: An over-the-counter health product, Dental equipment and supplies. Book 2 reference: Chapter 11. Checked 11 October 2026.
Mexico raises duties on non-treaty goods across hundreds of lines
A decree of Congress raised Mexico's general import duty on a long list of tariff lines for goods that cannot claim a trade agreement. Among the lines read in the decree: cosmetics 3304.99.01 and 3304.99.99 at 25 percent, cotton T-shirts 6109.10.03 at 35 percent, toys of heading 9503 and playing cards 9504.40.01 at 30 percent. Goods with proved treaty origin keep their preferential rate.
Source: Diario Oficial de la Federación, as published by the Cámara de Diputados. Industries: Beauty and personal care, Toys, hobby and collectibles, Products that face a closed door. Book 2 products: Korean skincare, Japanese anime and hobby collectibles, Generic T-shirts and apparel. Book 2 reference: Chapter 3. Checked 11 October 2026.
Courier rates for 2026: free to US$50 for USMCA parcels
Under the 2026 foreign-trade rules, a courier parcel from a USMCA country worth up to 50 dollars enters with no duty and no IVA, paying the processing fee; from 50 to 117 dollars a single rate of 17 percent applies, and 19 percent above. Parcels from countries without a trade agreement pay a single rate of 33.5 percent. Goods subject to permits or NOMs cannot use these rates.
Source: Reglas Generales de Comercio Exterior para 2026, rule 3.7.35, via SIDOF. Industries: All industries. Book 2 products: Hand-made bass fishing lures, Generic T-shirts and apparel. Book 2 reference: Chapters 7 and 13. Checked 11 October 2026.
Customs law reform widens broker liability and paperwork
A reform of the Ley Aduanera makes the partners of a customs agency jointly liable for duties on the operations it handles, requires a full electronic file proving each import, and sets the broker's licence at 20 years, renewable. Most of it applies from 1 January 2026, with some articles one or three months later.
Source: Diario Oficial de la Federación, via SIDOF. Industries: All industries. Book 2 products: all fifteen. Book 2 reference: Chapter 15. Checked 11 October 2026.
A primary source here is the Diario Oficial de la Federación, the issuing body's own page, or the official consolidated text. Law-firm notes and the press may point us to an entry; they are never its source.
What's Changing, by email
A dated note when a rule, tariff, wage or figure that matters to doing business in Mexico changes. At most twice a month, and only when something moves. The free Mexico Pack comes with it.