The TUI has unanimously supported an emergency motion calling for a rejection of the proposed public service agreement, while the INTO narrowly defeated a similar motion.
At their annual conference in Ennis, TUI delegates voted for the motion, which instructs the executive committee to ballot members recommending rejection.
The TUI represents 15,000 teachers who work in vocational and community secondary schools, PLC colleges and in Institutes of Technology.
The union says 1,200 teachers have lost their jobs at second level. It claims that salaries have been driven down by 20% when the pension levy, pay cuts and unpaid increases are taken into account.
A similar motion calling for the rejection of the public service pay deal was defeated by a narrow margin at the INTO annual congress.
The emergency motion was rejected by a margin of just four votes - 308 to 304.
The session was held in private.
Earlier, Minister for Education Mary Coughlan was heckled by teachers during an address at the conference in Salthill, Co Galway.
The Minister told teachers Ireland will have less to spend on public services for the foreseeable future.
However, she insisted that social cohesion had to be maintained and warned against what she called dangerous divisions.
Around 100 delegates held up placards critical of the Government's economic policies.
The Minister's speech was punctuated by frequent and loud heckling and booing from the floor.
Meanwhile, the Association of Secondary Teachers in Ireland began its annual conference this afternoon.
Its members will make a decision on the pay and reform proposals at a session tomorrow.
