Tax on rental income from abroad

Hi there. Help me settle an argument with my fiancee. She is Polish and living here 8 years. She has worked that entire time as a nurse. So she just pays PAYE tax etc.
However she owns a house in Poland that she inherited and has rented out to students. Every month she just takes out the rental money in cash with her Polish bank card. She says she doesn't have to pay tax on it here because the house is in Poland. I reckon she should have to as she lives in Ireland so all sources of income should be taxed here - am I right?

From what you say your fiancée is resident and ordinarily resident in Ireland.

She may or may not be domiciled here. A non-domiciled person is only liable to tax on foreign sourced income (such as rental income in Poland) to the extent that it is remitted (i.e. brought) into the country.

Since she has brought the money to Ireland she has made the question of her domicile irrelevant, and she may have a tax liability here. She would be entitled to deduct any income tax she has to pay in Poland from her Irish liability.

If she doesn't want her Polish rents to be taxable here, she needs to establish that she is still Polish domiciled, and keep that money outside of Ireland.