The umbrella organisation takes in Higgins' Socialist Party and the campaigning People Before Profit group.
Sinn Fein has ended up with at least 13 seats, while a number of left-leaning candidates such as Luke 'Ming' Flanagan were also successful.
The left-wing Independents (including the ULA) were expected to discuss forming a technical group which would give them special speaking rights in the Dail.
However, there is unlikely to be too much cooperation with Sinn Fein.
The ULA states it wants to provide "a real alternative" to Labour and SF, who "accept the capitalist market and refuse to rule out coalition with right wing parties".
Joan Collins, who was elected to Dublin South Central, made clear following her victory that the ULA was separate from SF.
The alliance has insisted it will "not do any deals or support any coalition with any of the right wing parties particularly Fianna Fail and Fine Gael".
"We are committed to building a mass left alternative to unite working people, whether public or private sector, Irish or migrant, with the unemployed, welfare recipients, pensioners and students in the struggle to change society," it says.
Not surprisingly, the ULA is opposed to the outgoing government's banking policy.
"The ULA says scrap NAMA and end the bailout of the banks and developers. Take the banks, finance houses, major construction companies and development land into democratic public ownership and use them for the benefit of people, not the profit of the few," the alliance states. Boyd Barrett (43), elected in the Dun Laoghaire constituency ahead of Mary Hanafin (FF), has been the poster boy for leftwing causes for years.
But his big breakthrough only came at the local elections in 2009 when he was elected to Dun Laoghaire/Rathdown County Council.
His first move may well be to invest in a suit as he doesn't own one and TDs are required to dress smartly. Ming Flanagan (39), best known for his campaign to legalise cannabis, said his election in Roscommon-South Leitrim would inspire others to go forward in future.
He instantly declared he would take a 50pc pay cut in his €92,000 TD's salary.
Flanagan also called on all new TDs to do the same, saying the country couldn't afford the salaries currently paid to Dail members.