Ireland: how days are counted

At a glance

The test: 183 days or more in a tax year, or 280 days or more across the tax year and the one before (TCA 1997 s819).
Period: Tax year = calendar year, 1 January to 31 December. The second test also looks at the previous year.
What counts as a day: Any part of a day in the State. Time spent only airside in an airport or port does not count.

The rule

Under TCA 1997 s819(1), an individual is resident in the State for a tax year if present for 183 days or more in that year, or for 280 days or more in that year and the previous year combined.

Section 819(2) sets a floor. A year with 30 days or fewer in the State cannot count as resident under the 280-day test, and that year is left out of the two-year total. So the second test needs more than 30 days in the current year.

Since 2009, a person is present for a day if present at any time during that day (s819(4)(b), added by Finance (No. 2) Act 2008 s15). Revenue says airside time in an airport or port is not presence, and that a person prevented from leaving by unforeseen events, such as a storm or aircraft breakdown, is not counted on the day after the planned departure.

Separately, a person who has been resident for three consecutive tax years becomes ordinarily resident from the fourth year, and stays so for three consecutive years after leaving. Ordinary residence can matter even in a year when neither day test is reached. A person arriving can also elect to be treated as resident under s819(3).

How Atrium counts it

Atrium counts a day when any part of the calendar day is spent in Ireland, including arrival and departure days. It shows the nearest of the two conditions and how many days are left before it is reached.

For the 280-day test Atrium uses the recorded days of the previous year, or a figure you state for a year it does not hold. It leaves out a previous year of 30 days or fewer, as s819(2) does, and needs at least 31 days in the current year.

A trip you mark as transit counts as zero days. Atrium cannot tell airside from landside, so a landside connection marked as transit is left out. Atrium does not apply the day-after-delay rule. It flags that ordinary residence may apply from your past-year answers, and leaves that decision to your adviser.

What catches people out

Staying under 183 days in one year does not end the matter. Two years combined can reach 280.
A very short stay counts as a whole day. Landing late on the last evening of a trip still uses a day.
Passing through immigration, even briefly on a connection, is presence. Staying airside is not.
Ordinary residence can continue for three years after you leave, and it is a separate question from the day tests.
Years before 2009 were counted differently (present at the end of the day).

Cases

Decided case

A locum consultant working in Ireland, 2016 to 2019

Tax Appeals Commission (Appeal Commissioner) · 2023 · 84TACD2023, determination of 19 April 2023 Source

A consultant working as a locum in Ireland from 2016 appealed income tax assessments for 2016 to 2019 totalling EUR 263,178.59. He said he was resident in another country and relied on the double taxation agreement. In cross-examination he accepted that he spent 260, 334, 312 and 336 days in Ireland in those four years. The Commissioner found him resident in Ireland under s819(1)(a), then applied the treaty tie-breaker, found his habitual abode was in Ireland, and upheld the assessments. The Commission was later asked to state a case for the High Court.

The 183-day test was settled by figures the appellant accepted. The dispute moved to the treaty tie-breaker, where days spent in each country were again decisive.

Sources

Based on the sources above, last reviewed on 2026-10-04. Educational content, not tax advice. Atrium counts days; whether those days make you resident is for you and your adviser to decide.

Count your days in Atrium