Even though sending or receiving money is an everyday activity, many people don’t realize that, in some cases, it can have tax consequences.

The truth is, under certain circumstances, SAT (Mexico’s Tax Administration Service) can tax bank transfers or issue penalties. This can happen with loans, transfers between your own accounts, or deposits from abroad. That’s why we’re outlining situations where you could run into trouble with SAT—and how to prevent it.

SAT and Transfers: When They Can Lead to Fines and How to Prevent Them

When Can the SAT Fine You for Transfers?

Today, discussing SAT and bank transfers is crucial for any Mexican looking to avoid tax issues. There are at least 6 situations where fines may apply:

1. Amounts over 15,000 MXN

Cash deposits totaling more than 15,000 MXN per month are reported by banks to SAT. This doesn’t mean you’ll automatically be penalized, but it could raise red flags if not declared or justified.

If you don’t have invoices, receipts, contracts, or supporting documents, consequences include:

• Fines ranging from 1,400 to 34,730 MXN for not reporting income.

• A 3% tax on the transferred amount.

Although this doesn’t refer directly to taxes on electronic transfers, your bank activity must match your official income. Otherwise, SAT could initiate an audit.

2. Loans or donations over 600,000 MXN

Any transfer, loan, or donation exceeding 600,000 MXN in a year must be reported within 15 days of receiving it. If not, SAT may consider it undeclared income, which could lead to:

• Fines ranging from 50% to 75% of the unreported amount, plus interest.

• Additional penalties of up to 35,000 MXN per unreported transaction.

For example, if a family member lends you 650,000 MXN and you don’t report it, you could face a heavy penalty.

3. Transfers Between Your Own Accounts

It might seem harmless, but even transfers between your own accounts can have consequences, especially when over 15,000 MXN.

If the bank spots movements without clear justification, it can notify tax authorities. SAT may then assume you’re receiving extra income and ask for proof—even if it’s just between your accounts at different banks.

You must prove the source to avoid:

• A 3% fine on the amount.

• Penalties from 1,400 to 34,730 MXN for each suspicious operation.

If the SAT wants to go deeper, it can escalate to a cabinet review.

4. Inappropriate Transfer Descriptions

You can also raise red flags with the wording you use in transfer descriptions.

This isn’t just a minor detail—banks and tax authorities monitor certain terms that may raise suspicions. Especially those referring to illegal activity (e.g., drugs or money laundering), or overly vague or joke entries.

Writing something the bank deems suspicious could trigger a review. If you can’t prove the origin of the money, you’re in trouble.

In such cases, you could face the same consequences as with unjustified transfers: a 3% fee on the amount and fines of up to 34,730 MXN per operation.

5. Transfers from Abroad or Unusual Activity

If you receive money from abroad that doesn’t match what you’ve declared to SAT, you may be audited. The same applies to banking activity that doesn’t align with your tax profile.

Say you report monthly income of 15,000 MXN and suddenly receive a 100,000 MXN bank transfer. That’s likely to alert your bank immediately.

They would then notify the Financial Intelligence Unit (UIF) and SAT—especially if the transaction appears unusual or lacks clear justification.

• Fines range from 1,400 to 34,730 MXN per operation.

• In more serious cases, where there’s suspicion of tax evasion or money laundering, fines can reach up to 173,230 MXN.

They may even freeze your account if the transaction is deemed risky.

6. Failing to File Your Annual Return

Lastly, if you omit loans, donations, or other income in your annual tax return, SAT may assume you're hiding something. Even transfers between family or your own accounts must be reported.

Failing to include these can result in fines up to 34,730 MXN per unreported transaction, plus interest and the potential for a full audit.

How to Avoid SAT Fines for Transfers

Avoiding SAT penalties for transfers means more than just keeping receipts—it requires clarity, foresight, and strategic action.

Here are some essential tips:

Keep Proof of Your Transactions

The most important thing is to have evidence for any transaction that exceeds the allowed limits.

This includes:

• Invoices, receipts, contracts, or bank statements supporting the movement.

Don’t wait for SAT to request them—set up a clear filing system, either on your computer or in the cloud via services like Google Drive.

Make It Official, Even Between Friends or Family

If you're selling something or receiving a loan, draft a basic contract that outlines the reason, amount, and names of both parties. It doesn’t matter if it’s between relatives or friends—create a document and keep a copy of both IDs.

Store the file for at least five years—the timeframe SAT can audit your financial history. After that, you're no longer required to present it, unless under special circumstances.

Monitor Your Tax Mailbox

Any notices, requests, or audits will be sent directly to your SAT tax mailbox. So check it frequently to respond on time.

Activate it using your e.signature and link it to your email and phone number if you haven’t already. That way, you’ll receive notifications.

Act Quickly

If SAT asks for clarification, you have 15 business days to respond. So, stay organized and be ready to send documents or schedule an in-person appointment when notified.

Report Large Transactions Without Delay

If you receive more than 600,000 MXN in loans, donations, or contributions in a year, report it. You can file it online with your e.signature on SAT’s portal using Form 86-A.

Match Your Tax Return to Your Banking Activity

Discrepancies between your income and what you declare can trigger a tax review—even for exempt amounts like loans or donations.

Before filing:

• Check your bank statements and make sure you've declared and justified all income, especially amounts over 15,000 MXN.

• While loans, gifts, or inheritances aren't subject to ISR, they must be reported in the exempt income section.

• Use SAT’s simulator to catch errors or omissions before submitting your return.

Avoid filing your annual SAT return out of time, as there are also consequences for doing so.

Get Help When Things Get Complicated

If you receive frequent transfers, handle large amounts, or have income from multiple sources, it’s best to consult a tax expert.

An accountant can help you stay compliant and catch issues before SAT does.

Can’t afford one?

SAT offers free assistance through its help channels on their website.

Conclusion

SAT and bank transfers don’t always mean automatic penalties—but they do involve constant oversight.

And while SAT doesn’t automatically tax bank transfers, it can fine you for unexplained or unusual operations—from family loans to transfers between your own accounts at different banks.

To avoid issues or fines, be fiscally responsible. This includes keeping documentation that validates your income, whether it exceeds permitted limits or not. Also, file on time and ensure your bank activity aligns with your reported income.

If you're handling international transfers, you might want to consider more practical methods. Our app could be an alternative you’ll appreciate for sending or receiving money in foreign currencies.

DolarApp lets you open a digital dollar account from Mexico, Argentina, Brazil, or Colombia—perfect for managing international transactions.

You can send or receive money from another country for just 3 USDc per transaction. Your balance stays in your digital account, and you can convert it to your local currency whenever you want—at a fair, real-time exchange rate.