The window to comply with Mexico’s aggressive 2026 tax reform is closing rapidly. Starting January 1, 2026, the Mexican Tax Administration Service (SAT) will require digital platforms like Amazon and Mercado Libre to act as strict tax enforcers. Under this new mandate, sellers who fail to upload a valid RFC (Mexican Tax ID) to their Seller Central accounts will face a severe financial penalty: a combined withholding rate of 36% on their gross sales. This punitive measure is designed to force informal and unregistered sellers into the tax system immediately, leaving no room for delay.
Why You Face a 36% Deduction
If your account is flagged as "Non-Registered" or "Invalid RFC" by Jan 1, platforms are legally obligated to withhold:
- 16% VAT (IVA): The full standard value-added tax.
- 20% Income Tax (ISR): A maximum penalty rate applied to total sales.
- Total Impact: 36% of every dollar you sell is removed before you see a penny.
Note: For compliant sellers with a valid RFC, the withholding rates drop significantly—typically to a manageable 8% VAT and a sliding scale for income tax.
Amazon’s Hard Deadline: December 26, 2025
Although the law officially takes effect on New Year's Day, Amazon Mexico has issued a critical alert requiring sellers to upload their valid RFC ID and Constancia de Situación Fiscal (CSF) by December 26, 2025. This buffer period is essential for Amazon to validate seller tax status against the SAT database before the new tax cycle begins. Sellers who miss this December 26 cutoff risk having the full 36% withholding applied to their first payouts in January, with no option for retroactive refunds on taxes withheld due to late registration.
Remote Fulfillment (NARF)
For U.S.-based sellers, the Remote Fulfillment with FBA (NARF) program remains a critical strategic lifeline. The new withholding rules apply specifically to products shipped from a storage address within Mexico. If you ship via NARF, your inventory remains in U.S. warehouses, meaning the customer acts as the importer of record and pays duties at checkout. Consequently, NARF sellers generally do not trigger a taxable nexus in Mexico and are exempt from the 36% withholding. However, if you store even a single unit in a Mexican warehouse (via FBA Mexico or Mercado Libre Full), you are considered to have a taxable presence and must register for an RFC to avoid the penalty.
Sellers must act immediately to verify their inventory status. If you have stock sitting in a Mexican fulfillment center, you are liable. The priority is to upload your CSF to Seller Central before the December 26 deadline. For those who do not intend to register for a Mexican tax ID, it is vital to audit your account settings to ensuring "Remote Fulfillment" is active and that no accidental returns have created "stranded inventory" inside a Mexican warehouse, which could inadvertently trigger these steep tax penalties.
11 Dec, 2025
