The call comes as a substitute teacher says she can't afford to stay in the career.
The exodus of teachers from Ireland will continue, unless they're offered permanent contracts.
The Teachers Union of Ireland's warning comes after a midlands teacher reached out to Midlands 103 with concerns she would have to give up the career, as she couldn't secure full-time work.
She says she can't afford to live solely on substitution work.
General Secretary of the TUI, and Tullamore's Michael Gillespie, says offering teachers a full-time contract isn't educationally unsound: