Aodhán Ó Ríordáin of Labour has lost his Dáil seat in Dublin Bay North.
The junior minister had been tipped as a potential party leader.
Instead, the final seats went to Sinn Fein's Denise Mitchell, and Independents Tommy Broughan and Finian McGrath.
This leaves the Labour Party with six seats - one short of the seven needed for Dáil speaking rights.
Nationally, there are just two seats left to be filled in the 32nd Dáil - with counts and re-counts continuing in two constituencies.
In Longford-Westmeath, a second re-count is underway with a razor-thin margin of votes between Labour's Willie Penrose and Fine Gael's James Bannon.
While disputed votes are at the centre of the delay in Dublin South Central, where it is between People Before Profit candidate Bríd Smith and Fianna Fáil's Catherine Ardagh for the fourth seat.
Meanwhile, the outgoing Cabinet will meet this afternoon - including three ministers who lost their seats.
James Reilly, Alex White and Ged Nash are no longer TDs.
The Taoiseach Enda Kenny is expected to ask his Fine Gael ministers for permission to begin talks with smaller parties to form a government.
Under the Constitution, the outgoing Taoiseach and ministers remain in their roles until a new Taoiseach is elected and a government formed.
Speaking after his elimination, Mr Ó Ríordáin said he is disappointed - but it is clear the people do not want Labour in government.
He also tweeted to congratulate his rivals:
Congrats to Denise, Richard, Finian, Seán & Tommy.
So proud of our campaign, our party & our values.@labour #dubbn pic.twitter.com/0CQ1498JhY— Aodhán Ó Ríordáin TD (@AodhanORiordain) March 1, 2016
