The 700,000 UDI Capital Gains Exemption on a Mexico Property Sale

Mexico's capital gains exemption on a primary residence is commonly referenced as "700,000 pesos," but it is actually measured in 700,000 UDIs, an inflation-indexed unit worth far more than one peso. In practice the exemption shields several hundred thousand US dollars of gain from ISR when you sell your primary residence. Understanding the UDI distinction is essential, because it makes the exemption much larger than the "pesos" shorthand suggests. Here is how the limit really works.

UDIs, not pesos

The UDI (Unidad de Inversión) is a unit of account indexed to inflation. Because each UDI is worth substantially more than one peso, 700,000 UDIs translates to a peso figure in the millions, which in turn equals several hundred thousand US dollars. So the exemption is far more generous than "700,000 pesos" implies. The UDI value updates over time with inflation, so the dollar amount of the shield gradually rises.

How the limit applies to your gain

When you sell, ISR is owed on the net gain, the sale price minus your inflation-adjusted purchase price, documented improvements, and acquisition and selling costs. The primary-residence exemption then removes up to the 700,000-UDI ceiling from that net gain:

• If your net gain is at or below the UDI ceiling and you qualify, the gain can be fully exempt.
• If your net gain exceeds the ceiling, only the excess is taxed under ISR.

This structure means many ordinary primary-residence sales owe little or no Mexican capital gains tax at all.

A worked example

Suppose you bought an oceanfront residence at around half a million USD and sell years later at $540,000:

• Gross difference: $150,000.
• After inflation adjustment on the original cost plus documented improvements and selling costs, the net taxable gain shrinks, say to roughly $110,000.
• If that net gain sits within the ~700,000 UDI exemption and you meet the primary-residence requirements, the entire gain can be exempt from ISR.

The example shows why documentation and the UDI-based ceiling together often eliminate the tax for a qualifying seller.

Who qualifies

The exemption applies to a primary residence, and foreigners can qualify when holding through a fideicomiso, provided they prove the home was their primary residence. Typical proof includes utility bills and bank statements in your name at the address, plus a valid RFC tax ID. The exemption is generally usable once per period (commonly three years), so timing matters if you own multiple properties. Learn how the buying process sets this up on our investment overview.

Why the distinction protects you

Buyers who think the exemption is only "700,000 pesos" sometimes assume it is too small to matter and skip the documentation needed to claim it. In reality the UDI-based ceiling is large enough to shield most primary-residence gains, so the paperwork is well worth maintaining. Keeping facturas for improvements, recording the true purchase value, and holding the property in your name all preserve access to this substantial benefit.

Plan from the moment you buy

The exemption rewards owners who set up correctly at purchase. A transparent developer that documents the full transaction value and supports your RFC and residency paperwork makes claiming the exemption straightforward when you eventually sell. Explore how Viento structures ownership on our residences page.

Get a tailored estimate

Whether your gain falls under the UDI ceiling depends on your specific numbers and documentation, so a personalized review is essential, particularly if you also report the sale in the United States. Want to understand the full ownership and exemption picture for a Viento oceanfront condo at El Sauzal? Schedule a private visit and our advisors can guide you. Reach us on WhatsApp or via our contact page to book your tour.