That's according to the latest Census figures.
The latest Census figures show that there were over 5.1 million people in the State on Census night, which took place in April last year.
That is an 8% (387,274 people) increase on April 2016 figures.
County Kildare's population increased by 11%, while the county continued to be one of the counties with the youngest age on average, at 36.9.
Nationally, the population includes more females than males.
There are 2.6 million females living in the country compared to 2.5 million males.

Kfm Obituary Announcements
Construction Of Clane Community Library Has Been Launched
Just One Special Class Allocated To Kildare Out Of 40 Announced Nationwide
Kildangan GAA Asking For People To Share Pictures For New Commemorative Book
Ryan Murphy Pleads Guilty To Manslaughter Of Ryan Weir Gibbons
Gardaí Investigating Two Incidents In Athy Totalling €7000 In Damage
McGregor Settles Whiskey Dispute With Lobov
School Bus Fees To Double For Primary School Children From September