When two countries treat you as resident

What this covers

Dual residence means two countries each consider you tax resident under their domestic rules. It is common in the year of a move and for people with homes or family in two places. The European Commission's Your Europe guidance says that in some cases two countries could consider you resident at the same time and both may tax your worldwide income. Treaties do not stop either country applying its own law. They decide residence for the purposes of the treaty and set out how double tax is relieved.

See how two countries can both count you

Each country uses its own tests. One may count days in a calendar year, another days in a rolling 12 months, and a third may look at your home or economic interests without any day count. Meeting one test in each country is enough to be resident in both.

Spain's Agencia Tributaria explains that treaties refer back to each country's domestic law to define who is resident, so two states can consider the same person resident. It then describes the order of tests that treaties usually use to resolve the conflict.

Start by writing down, for each country, which test you may meet and on what facts. The exposure check can help you list them.

Work through the treaty tie-breaker tests in order

Article 4(2) of the OECD Model Tax Convention sets out tie-breaker tests for individuals. Many treaties follow it, but each treaty has its own wording, so read the actual treaty between your two countries. See the tie-breaker rule entry.

Under the Model, you move to the next test only if the one before does not give an answer.

• Permanent home. You are resident only of the state where you have a permanent home available to you.
• Center of vital interests. If you have a permanent home in both, you are resident of the state with which your personal and economic relations are closer.
• Habitual abode. If the center of vital interests cannot be found, or you have a permanent home in neither, you are resident of the state where you have a habitual abode.
• Nationality. If you have a habitual abode in both or neither, you are resident of the state of which you are a national.
• Mutual agreement. If you are a national of both or neither, the two competent authorities settle the question by mutual agreement.

Understand what a tie-breaker result does and does not change

The tie-breaker decides residence for applying the treaty. It does not always change your status for every domestic purpose. The UAE's Cabinet Decision No. 85 of 2022 says that where an international agreement sets conditions for tax residency, those conditions apply for the purposes of that agreement.

The IRS gives a US example for people who are not US citizens. Publication 519 says that if you are treated as a resident of a foreign country under a treaty, you are treated as not resident in the US when figuring your US income tax, but as a US resident for other purposes. It says a dual resident claiming treaty benefits files Form 1040-NR with Form 8833 attached, and notes that this can trigger section 877A expatriation tax for some long-term residents.

US citizens are in a different position. The IRS says most treaties have a saving clause that preserves each country's right to tax its own citizens as if the treaty were not in effect. See the saving clause entry.

Get proof of residence before a country asks for it

To claim treaty benefits, the other country often wants a certificate from your residence country's tax authority. Each authority has its own process and conditions.

Look at how each country gives relief for tax paid

Treaties assign taxing rights income by income. Where the other country may tax an item, the residence country gives relief. The OECD Model offers two methods. Under Article 23 A the residence country exempts the income, with a credit for some items such as dividends and interest. Under Article 23 B it allows a deduction from its own tax equal to the tax paid abroad, capped at its own tax on that income.

Domestic credits work alongside treaties. The IRS says you may be able to take a credit or an itemized deduction for foreign income taxes paid on income also subject to US tax, claimed by individuals on Form 1116. It says only income, war profits and excess profits taxes qualify for the credit.

Relief depends on the order in which countries tax and on timing. Ask a professional which country gives relief on each item and when.

Know where to turn if the two countries disagree

Treaties contain a mutual agreement procedure for taxation that does not follow the treaty. Under Article 25(1) of the OECD Model, a person who considers that one or both states will tax them not in accordance with the treaty may present the case to the competent authority of either state, whatever remedies domestic law offers. The Model says the case must be presented within three years from the first notification of the action. Real treaties may set different time limits.

The competent authority tries to resolve the case itself or by agreement with the other country. Under Article 25(5) of the Model, unresolved issues can go to arbitration after two years if the person asks in writing, but only where the treaty includes that paragraph.

In the US, the Internal Revenue Manual says the MAP articles in US treaties give taxpayers the right to ask for help from the US competent authority, and that Rev. Proc. 2015-40 sets out how to make the request.

Common misconceptions

Questions to take to a professional

1. Under each country's own rules, which residence tests do I meet, and from which dates?
2. Is there a tax treaty between the two countries, and how does its residence article read?
3. Where do I have a permanent home available, and which way do my personal and economic relations point?
4. Which certificates of residence do I need, from which authority, and for which periods?
5. Which country taxes each item of my income under the treaty, and how is relief given?
6. Do I need to disclose a treaty position on my return, for example on IRS Form 8833?
7. If both countries still tax the same income, is a mutual agreement procedure open to me, and by when?

Questions people ask

Sources

• Model Tax Convention on Income and on Capital: Condensed Version 2017 (OECD)Treaty text
• Your Europe: Income taxes abroadOfficial guidance
• Agencia Tributaria: Persona física residente en EspañaOfficial guidance
• Publication 519 (2025), U.S. Tax Guide for AliensOfficial guidance
• About Form 8833, Treaty-Based Return Position Disclosure Under Section 6114 or 7701(b)Official guidance
• Tax treaties can affect your income taxOfficial guidance
• Form 6166: Certification of U.S. tax residencyOfficial guidance
• Apply for a certificate of residence or letter of confirmationOfficial guidance
• Issuance of a Tax Residency and Commercial Activity Certificate (Federal Tax Authority)Official guidance
• Cabinet Decision No. 85 of 2022 on the Determination of Tax Residency (FTA unofficial translation)Primary law
• Determining residency (Estonian Tax and Customs Board)Official guidance
• Foreign Tax CreditOfficial guidance
• 4.60.2 Mutual Agreement Procedures and Report Guidelines (Internal Revenue Manual)Official guidance