Capital Gains Tax When Selling Property in Mexico as a Foreigner (2026)

The Tax That Determines Your Net Proceeds

When you sell property in Mexico, the seller — not the buyer — owes capital gains tax, known as ISR (Impuesto Sobre la Renta). For foreigners this is the single biggest variable between “I made money” and “I broke even,” and it is the area where good planning saves the most. The tax can range from effectively zero to roughly 35% of your gain, depending on how you structured ownership and whether you qualify for the residency exemption.

The notary calculates and withholds this tax at closing, so you cannot ignore it. But you can plan for it — and many foreigners overpay simply because they never learned the rules.

How ISR on a Property Sale Is Calculated

You are taxed on the gain, not the sale price. In simplified terms:

Gain = Sale Price − (Adjusted Acquisition Cost + Documented Deductions)

The notary then applies ISR to that gain. There are two calculation methods, and the notary generally uses the one that produces the correct legal result:

1. A flat rate applied to the gain (commonly cited around 25% of the gross sale price in certain non-resident scenarios), or
2. A progressive rate on the net gain that can reach 35% at the top bracket.

For most sellers who can document their basis, the net-gain method is far more favorable than any flat-on-gross calculation.

The Game-Changer: The Residency Exemption

Mexican law provides a capital gains exemption on the sale of your primary residence (casa habitación). This is the strategy that legally reduces the tax to zero for qualifying sellers. To claim it you generally must demonstrate:

• The property was your actual primary residence
• You hold valid Mexican tax residency — typically evidenced by a temporary or permanent resident visa and, critically, a Mexican RFC (tax ID) with your address matching the property
• Proof of residence at that address: utility bills (CFE electricity, water, telephone) in your name showing the property as your home
• The exemption is subject to a value cap (a UMA-indexed ceiling, in the range of roughly 4–5 million pesos of gain in recent years); gains above the cap are still taxable
• You can generally use this exemption only once every three years

The requirement that trips up foreigners is not the visa — it is the paper trail proving residence. Tourists holding property on a tourist entry, or owners who never established a Mexican tax profile, do not qualify no matter how long they “lived” there in practice.

What You Can Deduct to Shrink the Gain

Even without the full exemption, you can substantially reduce taxable gain with proper documentation. Deductible items typically include:

• Original acquisition cost, indexed for inflation over your holding period
• Documented capital improvements — construction, remodeling, additions — supported by facturas (official CFDI invoices with your name and RFC)
• Notary fees and acquisition tax paid when you bought
• Real estate commission paid on the sale
• Certified appraisal and related closing expenses

The recurring theme: facturas or it didn’t happen. A $60,000 renovation paid in cash to an informal contractor with no CFDI invoice is, for tax purposes, invisible. It will not reduce your gain by a single peso.

Worked Example

A foreigner sells a condo for $400,000 USD, bought years earlier for $250,000 USD, with $40,000 USD of properly invoiced improvements and $20,000 USD in documented selling costs.

Scenario	Taxable Gain	Approx. Tax Owed	Net After Tax
No documentation, flat method	~$400,000 (gross basis)	Very high (up to ~$100,000)	~$300,000
Documented basis, no exemption	~$90,000 net gain	~$27,000 (progressive)	~$373,000
Qualifies for residency exemption	$0 (within cap)	$0	~$400,000

The spread between the worst case and the best case here is roughly $100,000 USD — entirely a function of paperwork and planning done before the sale, not after.

The Notary’s Central Role

In Mexico the notary legally calculates, withholds, and remits the capital gains tax at closing. This is not optional and not something you settle later with the tax authority yourself. Practical consequences:

• The notary needs all your documentation up front — visa, RFC, utility bills, facturas for improvements, original purchase deed.
• Different notaries apply the rules with differing conservatism. It is legitimate and wise to consult a notary (or two) before listing to understand your projected tax.
• Do not assume your agent knows your tax position. The notary is the authority; get the calculation in writing.

Legal Strategies That Actually Work

• Establish residency and an RFC early if you might ever claim the primary-residence exemption. This cannot be retrofitted the week before closing.
• Keep every factura for improvements, with your name and RFC, in an organized file from day one.
• Time the sale around the three-year exemption window if you own multiple properties.
• Reconsider the corporation structure. Property held in a Mexican company sells as a business asset — the personal residence exemption does not apply. Great for rentals, costly at exit for a personal home.
• Index your acquisition cost. Inflation indexing over a long hold can meaningfully raise your basis and lower the gain; ensure the notary applies it.

The RFC and Residency: Start the Clock Early

The recurring lesson across every strategy above is that the exemption and deductions depend on documentation you must build years before you sell. The most valuable single action a foreign owner can take is to establish a Mexican tax identity early:

• Get an RFC (Registro Federal de Contribuyentes) tied to the property address as soon as practical.
• Secure residency (temporary or permanent) if you intend the property to be a genuine home.
• Put utilities in your own name — CFE electricity in particular is the utility the notary most commonly relies on as residence evidence.
• Keep this paper trail continuous. A gap where the property was rented out or bills were in someone else’s name can undermine a primary-residence claim.

None of this can be manufactured in the weeks before a sale. The owner who sets it up on day one has options the owner who waits does not.

Withholding for Non-Residents

If you have no Mexican tax residency at all and sell, the transaction is generally treated under non-resident rules, and the notary applies a withholding that can be calculated on the gross sale price rather than the net gain. This is often far more painful than the resident, net-gain calculation.

This is precisely why residency status matters beyond the exemption: even when you don’t qualify for a full exemption, being a documented tax resident with an RFC typically lets the notary use the more favorable net-gain method with your indexed basis and deductions — instead of a blunt tax on the gross price.

Reporting in Your Home Country

A word for US and Canadian sellers: paying ISR in Mexico does not end your obligations at home.

• US citizens must report the sale on their US return; foreign tax credits generally offset double taxation, but the reporting is mandatory.
• Canadians face similar reporting and credit mechanics.
• Currency conversion, cost-basis translation, and treaty provisions get technical fast — coordinate a Mexican notary/accountant with a home-country tax preparer well before closing.

Do not assume the Mexican tax is the whole story. Plan both sides.

What Doesn’t Work

• Underdeclaring the sale price to reduce gain — illegal, and it also shifts a larger future tax burden onto your buyer. Notaries increasingly refuse it.
• Claiming the residence exemption without the residency and utility paper trail. It will be denied.
• Relying on “the seller before me didn’t pay much.” Every sale is calculated on its own basis and documents.

The Bottom Line

Capital gains tax in Mexico is not a fixed penalty — it is a range, and where you land in that range is decided by decisions you make years earlier. The residency exemption can eliminate the tax entirely for a qualifying primary home, and even without it, disciplined documentation of your basis and improvements can cut the bill dramatically. The foreigners who overpay are almost always the ones who never kept the paperwork.

If you are thinking about selling — or even buying with an eventual sale in mind — the Mexico Living team can help you understand your projected ISR exposure and set up the documentation that protects your net proceeds. Book a call or reach out on WhatsApp before you list, not after.