an extract from Revenue.ie:
Tax residence status
Your tax residence status depends on the number of days you are in Ireland during a tax year.
You are resident in Ireland for tax purposes if you are in Ireland for a total of either:
Tax residence status
Your tax residence status depends on the number of days you are in Ireland during a tax year.
You are resident in Ireland for tax purposes if you are in Ireland for a total of either:
- 183 days or more in a tax year
- 280 days or more in a tax year plus the previous tax year taken together. With a minimum of 30 days in each year.
- Any time you remain 'airside'. This is when you remain in an airport or port (in transit) while you are in Ireland.
- Any time you are prevented from leaving on your planned day of departure. This is known as 'force majeure'. This could be due to sudden or severe weather conditions or the breakdown of an aircraft. You will not be regarded as being present in Ireland for the day after.