Avsec said its management would withdraw its lock-out notice to enable unions to formally ratify the pay offer with their members, which should take four to five weeks.
Civil Aviation director Graeme Harris, who negotiated with the unions alongside Avsec chairman Nigel Gould, said they had made a lot of progress today.
"We are pleased we have been able to find some common ground and hope the offer made today, which will be recommended by unions to their members, will lead to a formal settlement and in time a new collective agreement," he said.
"The travelling public can be assured we all wanted a constructive outcome and neither Avsec nor unions wanted to reach the point where strike action would cause any disruption to travellers during the school holidays."
The PSA said both unions would be recommending the agreement to their members.
The unions would also withdraw injunction proceedings along with their strike notices.