What to do if two countries still tax you twice

Key rules

• Deadline: The three years run from the first notice, so do not wait for appeals to end.
• Where to file: You send a written request to the competent authority of the country where you are resident, not to a tribunal. For a Spanish resident that is the Spanish Ministry of Finance.
• Appeals: This procedure does not replace Spanish appeals, so keep their deadlines.
• Final judgments: A final Spanish court decision cannot be overridden by the tax authorities.

When this route makes sense

The mutual agreement procedure is a last resort. Use it when two countries tax the same income and the treaty between them should have prevented that. It asks the tax authorities of both countries to agree on a fix. It has its own strict time limit and its own way to start.

The time limit

You must ask within three years of the first notice of the taxation that goes against the treaty. That first notice is often the assessment or the withholding. Write down that date now.

Most treaties follow this three-year pattern, but some older ones use a different period, such as two years, or a different starting point. Read the mutual agreement article in your treaty before you rely on the three years. For disputes between EU countries, the EU dispute-resolution rules also set three years from receipt of the first notification. If you file late, the request is refused as out of time and the treaty relief is lost.

How to start

You file with the competent authority of the country where you are resident. If you live in Spain, that is the Ministry of Finance, acting through the Dirección General de Tributos, and the AEAT's Oficina Nacional de Fiscalidad Internacional handles the case. If you live in the other country, you file there. Filing in Spain carries no state fee and no modelo payment.

Your request should include:

• who you are, the treaty, the years involved and the measure that caused the double tax;
• the facts, proof of the assessment or withholding, and what the other country has done;
• whether any appeal or other proceeding is pending;
• a clear request that the matter be resolved.

File it through the electronic register or in person. Ask for confirmation that it was received.

The procedure depends on the treaty and your tax residence, not on your immigration status, so EU, non-EU and UK Withdrawal Agreement citizens use it the same way.

How it relates to Spanish appeals

The two routes are separate and can run side by side. Keep every Spanish appeal deadline, such as the one month to appeal to the administrative tribunal (TEAR/TEAC), even after you file your request. Keep your Spanish appeals open until the Ministry accepts your request.

If an appeal is already open, the Ministry may pause the mutual agreement request until the Spanish decision. You can also withdraw the appeal so the request can go ahead.

A final court judgment can limit what the procedure can achieve.

The disputed tax while you wait

Collection of the disputed Spanish tax can be suspended during an appeal if you provide a guarantee. In some cases it can also be suspended during the mutual agreement procedure without a guarantee. Conditions and interest apply. Ask for suspension in your request.

Choosing between options

If you already have a Spanish appeal open, how do you handle your mutual agreement request?

• Run both together: You want to keep your Spanish appeal alive and also protect the treaty deadline; the request may be paused until the appeal is decided.
• Withdraw the appeal: You prefer a negotiated result between the two countries; a final court decision can then no longer help you.