Which residency calculator do I need?

Because the rules use different math. Most countries count days in a calendar year against a 183-day threshold, but Schengen uses a rolling 180-day window, the IRS Substantial Presence Test weighs three years of days, the UK combines day counts with ties, and New York pairs 184 days with a permanent place of abode. Each of those needs its own calculation.

That's common: a non-EU consultant working in Europe can face Schengen 90/180, a country's 183-day rule, and the US Substantial Presence Test in the same year. Run each applicable calculator, or use the multi-country day counter to watch several plain day-count thresholds at once.

Yes. Every calculator on this site runs entirely in your browser, with no signup and no upload. Nothing you enter leaves your device.

The web calculators are one-off checks: you type in your trips each time. The Tax Days iPhone app stores your trips privately on your device and evaluates them continuously against 80+ residency rules in 254 jurisdictions, projects the date you'd cross each threshold, and notifies you before it happens.

No. They compute day counts and rule thresholds from the dates you enter, which is general information, not advice. Residency outcomes can turn on facts beyond day counts, so confirm any real decision with a qualified professional.

Yes. Each country applies its own rules, so two can claim you in the same year, most often in the year you move. A tax treaty between them usually contains a tie-breaker that assigns you to one country for treaty purposes. Without a treaty, you can be fully resident in both and rely on foreign tax credits.

Sometimes, if you stay under every threshold and have no home or family anywhere that ties you. It is hard to sustain: your former home country may keep claiming you, and banks and brokers expect a country of tax residence. See the resident nowhere section above.

No. It is the most common threshold, but Thailand uses 180 days, India 182, Brazil and Colombia more than 183 in any 12 months, Cyprus has a 60-day route, and the UAE can make you resident after 90 days. Many countries also make you resident on fewer days if your home or family is there.

For most countries, no: residence depends on days and ties, not your passport. The United States is the big exception and taxes its citizens and green card holders wherever they live. Nationality also appears near the end of the treaty tie-breaker.

It is the part of a tax treaty that decides which country wins when both treat you as resident. It checks, in order, where you have a permanent home, where your vital interests are, where you habitually live, and your nationality. If none decides, the two tax authorities settle it by agreement.

It depends on the country. Many count any part of a day as a full day, the US counts any presence during a day, and the UK counts days on which you are present at midnight. Arrival and departure days are where most counting errors start.

Ask the tax authority for a certificate of residence, which most countries issue for treaty purposes. Back it up with a day-by-day travel log, leases, utility bills, employment records and bank statements. A record made at the time is far more persuasive than one rebuilt later.

Each country counts over its own period. Most use the calendar year, but the UK runs 6 April to 5 April, Australia 1 July to 30 June, India 1 April to 31 March, and several countries use any 12-month window. The tax year calculator shows the period for each country.

For anything borderline, yes. This checker simplifies each country's rules so you can see where you stand and which detailed test to run. Two-country cases, split years and US citizens abroad are worth a professional review.

Yes. It runs in your browser, nothing you enter is sent anywhere, and there is no sign-up. Tax Days, the iPhone app, tracks your days automatically if you want to keep the count current.