~/nerdy.money/guides/ tax-residency9 minchecked September 2026
Tax residency explained: 183 days, homes and tie-breakers
The 183-day rule is one test among many. How countries decide you’re resident, how treaties break ties, special rules and how to prove where you live.
“Tax residency” sounds like one thing. It’s actually two questions, asked separately by every country you’ve ever had contact with: does this country’s own law say you’re resident? And if two countries say yes, which one wins under the treaty between them?
This guide covers both questions, the special rules that trip people up, and how to prove where you really live. General information as of September 2026, not tax advice.
Why residency matters
Residency decides who taxes your worldwide income. Most countries tax residents on everything they earn anywhere, and non-residents only on income sourced in that country.
So when you move from a high-tax to a low-tax country, the whole plan hinges on two things: really ending residency in the old country, and really establishing it in the new one. For the German side of that, see leaving Germany.
The 183-day myth
The internet’s favourite rule: “Spend fewer than 183 days in a country and it can’t tax you.” That’s wrong often enough to be expensive.
Where does 183 come from? Many countries use “more than 183 days in a year” as one way to become resident. And double tax treaties use 183 days in a specific place: the rule for employment income (Article 15 of the OECD model), which decides when a country can tax salaries of short-term workers. Neither makes 183 days a general safe harbour.
What countries actually use:
Test
How it works
Example
Days of presence
Resident if you exceed a day count in the tax year or a rolling period
Many countries use 183 days; the UAE also has a 90-day test for people with residence permits and ties there
Home or dwelling
Resident if you have a home available to you, however often you use it
Germany: a home (Wohnsitz) makes you resident with zero minimum days
Habitual abode
Resident if you stay for a longer coherent period
Germany: more than six months in a row, even across two calendar years
Centre of interests
Resident where your economic or family life is
Spain: resident if your main business or economic interests are there; presumed resident if your spouse and minor children live there
Statutory test
A day count combined with ties
UK Statutory Residence Test
Citizenship
Taxed because of your passport
United States
The combination is what bites. You can be under 183 days in Germany and still German-resident because you kept your flat. Our day tracker helps you count – but counting is only part of the job.
When two countries claim you: Article 4 of the OECD model
Double residency is common: you moved to Portugal, but Germany still sees your old home. Most double tax treaties follow Article 4 of the OECD Model Tax Convention to decide which country you’re resident in for treaty purposes. The tie-breaker for individuals runs in a fixed order – you only go to the next step if the previous one doesn’t decide:
The treaty tie-breaker, step by step
Permanent home
Where do you have a permanent home available to you – owned or rented, used continuously, not just for short stays? If only in one country, that’s it.
Centre of vital interests
Home in both (or neither)? Then: where are your personal and economic relations closer? Family, friends, clubs, business, assets, where you work.
Habitual abode
Still unclear? Where do you habitually live – measured over a meaningful period, not just this year’s day count.
Nationality
Still unclear? The country whose national you are.
Mutual agreement
Still unclear (for example, you’re a national of both or neither)? The tax authorities settle it between themselves.
Three things to know about the tie-breaker:
It only works between two countries that both claim you. It never turns you into “resident nowhere”.
It needs a treaty. Without a treaty between the two countries, there’s no tie-breaker. Germany and the UAE, for example, have had no double tax treaty since the end of 2021.
It limits taxing rights, not paperwork. Your old country may still ask you to file and prove the treaty position.
Companies have their own tie-breaker based on where they’re managed: see place of management.
Special rules worth knowing
Cyprus: the 60-day rule
Cyprus lets you become tax resident with just 60 days a year, if in that tax year you:
spend at least 60 days in Cyprus,
don’t spend more than 183 days in any other single country,
aren’t tax resident in any other country,
carry on a business in Cyprus, are employed in Cyprus, or are a director of a Cyprus tax-resident company (and that doesn’t end during the year), and
have a permanent residence in Cyprus, owned or rented.
It’s popular with people who travel a lot. The catch is the third condition: you must really not be resident anywhere else, which brings you straight back to the home and habitual-abode tests of other countries.
The UK: Statutory Residence Test
The UK decides residency with a structured test that’s been in place since 2013:
Automatic overseas tests. For example, fewer than 16 days in the UK (if you were UK resident in any of the previous three years), fewer than 46 days (if you weren’t), or full-time work abroad under specific conditions. Meet one and you’re non-resident.
Automatic UK tests. For example, 183 days or more in the UK, or your only home is in the UK for a long enough period. Meet one and you’re resident.
Sufficient ties test. Otherwise, the number of UK ties (family, accommodation, work, 90 days in a previous year, and – for leavers – spending more time in the UK than anywhere else) sets how many days you can spend before becoming resident.
Since April 2025 the UK has also replaced the old non-dom remittance regime with a four-year exemption for foreign income and gains for new arrivals who weren’t UK resident in the previous ten years.
The US: taxation by citizenship
The US taxes its citizens and green card holders on worldwide income, wherever they live. Moving away doesn’t end that. Relief comes from the Foreign Earned Income Exclusion (an inflation-indexed amount of roughly US$130,000 of foreign earned income, if you meet the bona fide residence or physical presence test), foreign tax credits and treaties. Reporting obligations (FBAR, FATCA forms) apply on top.
Non-citizens can become US-resident through a green card or the substantial presence test, which counts days over a three-year window with weighting. For the full picture on US structures, see US LLC for Europeans.
The UAE: residency without income tax
The UAE has no personal income tax, but it defines tax residency for certificates and treaty purposes. Since 2023 you’re resident if your usual or primary residence and centre of financial and personal interests is in the UAE, or you spend 183 days there in a 12-month period, or 90 days if you’re a UAE or GCC national or hold a UAE residence permit and have a permanent place of residence or a job or business there. A UAE tax residency certificate is often what a bank or your old tax office wants to see.
Proving your residency
Tax offices and banks don’t take your word for it. What typically counts as evidence:
Evidence
Why it matters
Tax residency certificate
Official confirmation from the new country, often needed for treaty claims and banks
Long-term lease or property deed
Shows a permanent home
Utility and phone bills
Show the home is actually used
Residence permit and local ID
Show legal right to live there
Local tax ID and tax returns
Show you’re in the local system
Travel log with flight records
Proves days, and that you weren’t somewhere else
Local bank account, health insurance, gym, doctor
Show where your life happens
Deregistration in the old country
Shows the break, where registration systems exist
For the evidence in the other direction – that you’ve left – what you don’t keep matters as much: no flat available in the old country, no car registered there, no family home with “your” room.
Worked example: the 60-day plan
Sophie is German. She terminated her Berlin lease, deregistered, and set up a Cyprus company where she’s a director. She rents a flat in Limassol for the whole year. Her 2026 calendar:
Place
Days
Cyprus
75
Germany (visiting family, hotel stays)
55
Portugal
90
Other countries and travel
145
Total
365
Check against the rules:
Germany: no home available to her, no stay of more than six months. Not resident under German law.
Portugal: 90 days, no home there. Not resident.
Cyprus 60-day rule: 75 days in Cyprus, no more than 183 days in any other single country, not resident elsewhere, director of a Cyprus company, permanent residence in Cyprus. Resident.
Now change one fact: Sophie keeps her Berlin flat “for visits”. Germany now treats her as resident because of the home, so the Cyprus condition “not tax resident in any other country” fails, and the 60-day rule no longer applies. She’d have to rely on the ordinary Cyprus 183-day rule – which she doesn’t meet – and ends up resident only in Germany. Same days, very different outcome.
“Tax resident nowhere”: the fragile option
Some people end up resident in no country at all: they travel constantly, stay under every threshold and keep no home anywhere. Legally that’s possible. Practically, it creates problems:
Your old country may disagree. If you can’t show a new residency, the old tax office has an easy time arguing you never left.
No treaty protection. Treaties only protect residents of a treaty country.
Banks and the CRS. Banks ask for your tax residency and report accounts to that country under the Common Reporting Standard. “None” is an answer many banks won’t accept.
No residence certificate. Many business partners and platforms want one.
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