Mexican tax law (Article 93 of the Ley del Impuesto Sobre la Renta) lets you exempt up to roughly 5.85 million pesos of gain from Mexican capital gains tax when you sell your primary residence — approximately $325,000 USD at 2026 FX. On a typical American-owned beachfront property in Sonora or Baja, this exemption can wipe out the entire Mexican ISR bill.
It's also the most underused tax break American sellers leave on the table. Most owners don't realize they have to qualify before the closing — not in the days leading up to it.
Planning a sale in the next 1–3 years? Establishing residency now can save you tens of thousands at closing. Our team coordinates the residency, RFC, and primary-residence documentation strategy. Get a free consultation →
What the Exemption Does
If you qualify, your Mexican ISR is calculated only on the portion of your net gain that exceeds the cap. On a $300K gain that fully qualifies, the exemption excludes the entire gain — Mexican ISR is zero. On a $500K gain, only the portion above ~$325K is taxed.
This works alongside Method B (net-gain calculation), not against it. You still deduct your original purchase price, improvements with facturas, and selling costs first to arrive at net gain. Only then is the exemption applied to whatever remains.
Who Qualifies
All four conditions must be true at the time of sale:
- Mexican tax residency. You hold a Temporary or Permanent Resident card from INM and Mexico is your "place of habitual abode" for tax purposes. The INM card alone is not enough — you also need to be registered with SAT as a tax resident.
- Active Mexican RFC. The tax ID, with the property registered as your domicilio fiscal. RFC guide here.
- 3+ years of documented occupancy as your primary residence. Not "ownership" — occupancy. You must have actually lived there.
- No prior use of this exemption in the last 3 years. The exemption can only be claimed once every 3 calendar years.
The notario at closing will request proof of all four. If any one is missing, the exemption is denied for that sale and you pay the full Method A or Method B ISR.
Proving the 3-Year Occupancy
This is where most American sellers fail. INM card and RFC are documents you either have or don't. Occupancy is harder to prove because nobody tells you to collect the documents until you're at the closing.
The notario will look for at least three of the following, dated across the 3-year window:
- CFE (electricity) bills in your name at the property address. Continuous monthly bills are gold-standard.
- Telmex / phone / internet bills in your name.
- Property tax (predial) receipts in your name.
- Bank statements from a Mexican bank account showing the property address as your domicilio.
- Voting card (credencial INE) with the property address — possible if you're a permanent resident.
- Driver's license from the property's Mexican state, with the property address.
- Vehicle registration at the property address.
For American owners, the easiest path is usually: CFE in your name (set this up the day you close the purchase), Telmex in your name, and the property address on your Mexican bank account.
The Cap: 5.85 Million Pesos (Approximately $325K USD)
The cap is set in pesos and adjusted periodically. As of 2026, the figure is approximately 5.85 million pesos — equivalent to roughly $325,000 USD at recent FX (peso/dollar varies; check at time of sale).
What this means in practice:
- If your net gain is under $325K USD, the entire gain is exempt. Mexican ISR = $0.
- If your net gain is $500K USD, $325K is exempt and $175K is taxed at Method B progressive rates (~$30–$40K in ISR vs. ~$125K without the exemption).
- If your net gain is $1M USD, the exemption saves you roughly $60K in ISR — still material on a large sale.
Strategic Timing for U.S. Owners
If you're planning to sell within 1–3 years, the calculus is straightforward:
- Today: Apply for Temporary Residency at the Mexican consulate nearest your U.S. address. Approval typically takes 4–8 weeks, then you complete the residency in Mexico within 30 days. See the residency guide.
- Within 90 days of residency: Get your RFC at the SAT office.
- Move utilities into your name (CFE, Telmex, predial) at the property address.
- Spend enough time at the property to legitimately call it your primary residence (more than 183 days/year in Mexico, with the property as your specific domicilio).
- Wait 3 years from the date you can prove occupancy began (CFE bill in your name is usually the clean starting marker).
- Then list and sell.
On a $300K gain, this 3-year wait can save you $70K–$120K in Mexican ISR. On smaller sales, the math may not justify the residency cost ($600–$1,300 government fees + facilitator) and the lifestyle disruption.
The Non-Resident Reality
If you're a snowbird, weekend Sonora property owner, or someone who can't or won't establish Mexican tax residency, the exemption is not available to you. Period. You will pay either Method A (25% flat on gross) or Method B (~22% on net gain) — whichever is lower.
This is fine. Many American owners explicitly choose to remain U.S. tax residents (often for Medicare, Social Security, or financial reasons) and pay the Mexican ISR as a cost of doing business. The calculator shows both scenarios so you can compare.
Frequently Asked Questions
What to Do Next
- If a sale is more than 3 years away: start the residency clock now. The exemption only requires the residency at the moment of sale, but the 3-year occupancy clock won't start ticking until you can prove the property is your primary residence.
- If a sale is 1–3 years away: get residency and RFC immediately, even if you only spend part of the year at the property. Document everything.
- If a sale is imminent: the exemption almost certainly isn't available, but run the calculator with the resident/RFC boxes unchecked to see your real expected ISR.
- In all cases: collect facturas for every improvement you've made. They reduce the net gain you'd otherwise pay on under Method B, exemption or not.
Related reading: the complete seller's guide, Mexico residency for property owners, and how to get your RFC.
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