Their Laois-Offaly deputy says it costs the State hundreds of millions every year.
Sinn Féin is proposing new legislation to tackle bogus self-employment.
The practice involves employers misclassifying their staff as self-employed to avoid paying PRSI contributions, and cost the State an estimated 640 million over eight years in the construction sector alone.
Laois-Offaly TD and chair of the Oireachtas Public Accounts Committee, Brian Stanley says greater enforcement through legislation and Revenue is needed: