The CSO has also released the latest figure for the midlands region.
Ireland's population increased by just over one per cent in the year to April and now stands at 4.98 million.
That's an increase of 55, 900 compared to the previous year.
A third of the 85,400 people who immigrated to Ireland in that period were returning Irish nationals, the highest number since 2007.
12.9 per cent of the population are non-Irish nationals resident in the country.
According to the CSO, the population of the midlands region - Laois, Offaly, Westmeath and Longford - is now 304,000.
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