Fianna Fáil says it would abolish the 1% Universal Social Charge rate in its first budget after the election.
The party says it would also halve the 3% rate, with both measures costing €336m a year.
It says workers earning up to €80,000 a year would be taken out of the USC net altogether over five years.
Finance spokesman, Michael McGrath, says party is also proposing a 'rainy day fund' so that extra Corporation Tax receipts would be put away and used to stimulate the economy at any future downturn.
Mr McGrath said: "In essence, in the event of an economic downturn - which would be measured by a 1% increase in the unemployment rate, for example - that fund could be used as a buffer against any future economic shock.
"So, if any downturn does occur in the Irish economy, there would be a fund there that could be used for investment purposes and stimulate the Irish economy at a time of economic difficulty."