Overview
Mexico sits in a genuinely different category than the other five countries on this list — not clearly territorial like Panama or Costa Rica, and not clearly worldwide-and-unfavorable like Spain or Portugal. Mexico's treatment depends heavily on your specific residency status, and the Roth-specific answer is less confirmed than you might expect from how often Mexico is recommended as "tax-friendly."
Roth IRA Treatment — Unclear
This is the most important thing to understand about Mexico: no authoritative source in this research clearly confirms how Mexico treats Roth IRA distributions specifically. One general finance source suggests the US-Mexico treaty "generally recognizes the tax-deferred character of US retirement accounts," which would be relatively good news if confirmed — but this claim wasn't corroborated by any of the specialist cross-border tax firms researched, who instead focused their Mexico guidance on Traditional IRA, 401(k), and Social Security treatment without directly addressing Roth's unique tax-free status. The absence of a clear, repeated "Mexico taxes Roth growth" warning (the kind found consistently for Spain and Portugal) is a mildly encouraging signal, but it is not the same as a confirmed favorable answer.
Treat Mexico's Roth treatment as an open question requiring direct professional verification, not as either a known problem or a known non-problem.
Traditional IRA / 401(k) / Pension Treatment — Settled, with a Residency-Status Twist
This is where Mexico gets genuinely interesting: your Mexican tax residency status changes the answer.
- Temporary residents (most retirees, first several years): Mexico generally does not tax foreign-source income — including US Social Security, pensions, IRA, and 401(k) distributions — for those who are not Mexican tax residents under Mexican domestic law, which uses a "center of vital interests" test rather than a simple day-count.
- Permanent residents who become genuine Mexican tax residents: Mexico taxes worldwide income in theory, including private pension and IRA/401(k) distributions, per Article 19 of the treaty — with the US Foreign Tax Credit (Form 1116) available to offset Mexican ISR (income tax) paid on the same income.
The practical result for most American retirees: because Mexican tax residency isn't automatic just from holding a residency visa, and depends on where your "center of vital interests" genuinely sits, many retirees on Temporary Resident status pay no Mexican tax on their US retirement income at all.
Social Security Treatment — Settled
Under Treaty Article 19(1)(b), US Social Security benefits are taxable only by the paying state — the US. Mexico does not tax them, regardless of your residency status.
Wealth Tax Exposure — Settled
Mexico has no wealth tax, no inheritance tax, and no estate tax.
Key Planning Consideration
The residency-status distinction is the single most important planning lever in Mexico. Understanding whether you're likely to be classified as a genuine Mexican tax resident (versus simply holding a residency visa without triggering tax residency) materially changes your exposure — this is worth confirming with a Mexico-specific advisor before assuming either the best-case or worst-case scenario applies to you.
Recommended Advisor Type
A cross-border tax specialist who can assess your specific "center of vital interests" facts under Mexican domestic tax law — not just a general expat tax preparer, since the residency determination genuinely changes the answer here.
Sources
- Taxes for Expats — US-Mexico tax treaty guide for US expats (2026)
- Greenback Tax Services — Retire in Mexico: An American's Guide to Costs, Visas, Healthcare, and Taxes
- CountryTaxCalc — USA vs Mexico Retirement 2026
- Greenback Tax Services — Americans in Mexico: U.S. Tax Rules & Filing
This is general education reflecting a genuinely unresolved question (Roth treatment) and a residency-status-dependent answer (Traditional IRA/pension treatment). Work with a cross-border tax specialist to determine your specific Mexican tax residency status before relying on any assumption here.