There are 60 seats in the Seanad: 43 were elected on five vocational panels by serving politicians, for which polling closed on 25 April; 6 were elected in two university constituencies, for which polling closed on 26 April; and 11 were nominated by the Taoiseach (Enda Kenny) on 27 May 2016.

[4] Article 18.8 of the Constitution requires that an election for Seanad Éireann must take place not later than 90 days after a dissolution of the Dáil.

On 9 February, Minister for the Environment, Community and Local Government Alan Kelly signed the orders for the Seanad election.

[12][13][14] Government party denoted with bullet (●).Party giving confidence and supply denoted by C. The minimum parliamentary group size is five Senators, a threshold met by Fine Gael, Fianna Fáil, Sinn Féin, and the following three technical groups.

This group included Grace O'Sullivan (Green Party) until her election to the European Parliament in May 2019.

Labour formed a party group until the retirement of Denis Landy left it below the five-senator threshold.

It first formed a technical group with Trevor Ó Clochartaigh, who had resigned from Sinn Féin.

[22] When Ó Clochartaigh resigned from the Seanad, Labour recruited Norris,[23] who had left the Independent group shortly after the 2016 election.