About DoubleTaxation
DoubleTaxation is a free service that helps you find out which country you are a tax resident of, and where and which taxes to pay if you live, work or run a business abroad.
Why this project
Moving abroad, working abroad or temporary protection raise a simple question: where do I pay tax? The answer is scattered across the laws of two countries, a tax treaty and court practice, and a specialist’s advice costs money and time.
DoubleTaxation was created to let anyone check their tax residence abroad for free — so that everyone can understand their rights and obligations before going to a specialist or the tax authority.
What the service does
- Residency status between your home country and the country where you stay: the conclusion, how reliable it is and the legal rules behind it. 24 versions of the service by home country, 28 countries.
- Where and which taxes: what each country taxes and the treaty rules for each type of income — salary, business, pensions, dividends and more.
- Next steps: certificate of tax residence, obligations of residents and non-residents, steps when leaving, the year of the move, exit tax.
- Tax burden on salaries using the OECD method; preliminary data for countries outside the main list.
- Tax regimes for people who relocate, are self-employed, invest or receive a pension.
- Business taxes: sole proprietor or your own company compared.
- An Android app with a day-of-stay counter and an AI agent for Claude, ChatGPT and other assistants.
Methodology
The methodology is based on an analysis of national legislation and international treaties for the avoidance of double taxation. For each country, the rules are written as a sequence of questions under its law: home, centre of vital interests, days of stay, citizenship and so on.
If both countries consider you their resident, Article 4 of the treaty applies: permanent home → centre of vital interests → habitual abode → nationality → mutual agreement between the tax authorities. The conclusion also takes court practice into account. Details are on the Methodology page.
A smart law
The project is built as a “smart law”: legal rules turned into an algorithm. The conclusion is computed by a rules engine, not by an AI model, so the same answers always give the same result.
Every step relies on a specific legal provision with a link to the official text: you see not only the answer but also why it is what it is.
The aim is to improve people’s understanding of the law and make their lives easier: to understand their rights and obligations in plain words, without a law degree.
Sources and checks
Primary sources only: the laws and treaties in force, guidance from tax authorities and decisions of the highest courts. A second, independent check verifies every figure, deadline and provision, and before each release automated tests check the rules of every language version. Each page shows the date of the last check.
Privacy
No registration. Your answers are processed on your device and are not sent to a server. For statistics, we count only the country and the overall conclusion, anonymously. Details are in the privacy policy.
Independence
The project contains no advertising, does not promote any goods or services and receives no funding from third parties. The service is free, and its conclusions do not depend on anyone’s commercial interests.
Limits
The service is for information only and is not tax or legal advice. Tax authorities and courts may interpret the rules differently, and the law changes. Consult a specialist before making decisions.
Feedback
Found an error or an outdated rule, or have an idea? Write to us through the feedback form. We will check and fix it.