Michael D Higgins is now president-elect following the completion of the fourth count this afternoon.
He received 1,007,104 votes, exceeding the quota by 121,222.
The official announcement of Mr Higgins' victory was made in Dublin Castle after the results came in from all 43 constituencies.
The count for the two referendums on judicial pay and Oireachtas inquiries has now begun.
While early tallies show the amendment on reducing judges' pay is expected to be passed with a sizeable majority, the amendment on extending the remit of Oireachtas inquiries is too close to call, with some tallies suggesting it may be narrowly defeated.