CRYPTO & TAXES IN MEXICO
Crypto cost basis: how it is calculated
Direct answer
Your gain is the sale price minus your proven cost basis, adjusted for inflation (INPC) between purchase and sale. Without purchase records the gain and the tax can be computed on a much larger figure, so you end up overpaying.
What counts as proof of your cost
Your proven cost is what you actually paid for that crypto, backed by documents. The better the evidence, the closer the tax stays to your real gain.
It is not only the purchase receipt: dates, hashes and wallet addresses help rebuild the history when the platform no longer shows the operation.
- Exchange account statements (for example, Bitso statements).
- Purchase receipts or invoices.
- Transaction records: date, hash and wallet addresses.
- Commissions paid on acquisition, which can form part of the cost.
How the calculation works
The formula is: sale price minus proven cost, adjusted for inflation between the two moments. The INPC adjustment keeps the period inflation from being counted as your gain.
Generically: if you bought at one value, sold at another, and accumulated inflation between the two dates was a given percentage, your gain updates the cost by that percentage and subtracts it from the sale price. What remains is the base the ISR applies to.
Common mistakes that inflate your tax
The costliest mistake is having no records: with no proven cost, the gain is computed on the full sale amount. Next comes mixing operations from several wallets and platforms as if they were one.
It is also common to forget commissions paid and to leave crypto-to-crypto swaps undocumented. Each swap needs the peso value at that moment, because a gain can arise there too.
- Not keeping purchase records.
- Mixing wallets and platforms without separating each lot.
- Leaving out commissions that could add to the cost.
- Leaving crypto-to-crypto swaps without the peso value at the moment.
Frequently asked questions
Do commissions add to my cost basis?
They can form part of the acquisition cost, as long as they are documented. That is why it helps to keep the records where the commissions paid on purchase appear. Ask us in your consultation how to apply them to your case.
What if I bought years ago and kept nothing?
That is the most expensive scenario, because without evidence the tax can be computed on the full sale amount. It is still worth rebuilding the history: statements, emails, blockchain records and bank movements often provide data. We review your case in your consultation.
How do crypto-to-crypto swaps get cost basis?
Each swap is valued at the peso value of the crypto you gave up at that moment, and that value becomes the cost of the crypto you received. If you swap several times, tracking it lot by lot is the clearest approach.
Related questions
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Book your free consultationEducational content; not personalized tax advice.