EIS will issue a formal notice of the planned ballot to local authority employers next week, with ballot papers to be issued later this month.
The approval from the EIS Council was given at a specially convened meeting on Saturday.
Unions claim teachers’ pay has fallen 20% in real terms in the past decade, and say that a significant increase is needed to show teachers they are valued and to help boost staff recruitment and retention.
Earlier this week, the union rejected the latest pay offer from the Scottish Government and council umbrella body Cosla.
Education Secretary John Swinney said that the offer was “a better deal than for any group of public sector workers in the UK”.
EIS general secretary Larry Flanagan said: “EIS Council has today approved the opening of a statutory strike ballot over pay.
“We have been negotiating for a year, on a pay claim that was due to be settled last April. Teachers’ patience is now exhausted.
“Our preference has always been to agree a fair deal through negotiation, but we have been very clear, also, that we are prepared to take strike action should this be necessary to achieve an acceptable settlement.”
“Ballot papers will be issued later this month. Clearly, once the actual ballot is under way, negotiations are suspended but prior to that we remain prepared to consider any improved pay offer. No offer has been forthcoming from our local authority employers, however.
“Teachers have demonstrated time and time again their support for our Value Education Value Teachers campaign, which is about more than just pay. I’m confident that will continue to be the case.”
Mr Swinney said: “In light of concerns raised about the position of the significant number of teachers already at the top of the main grade pay scale, the Scottish Government is prepared to improve its offer around main grade restructuring and revaluation of all other SNCT pay scales.
“The Scottish Government will provide the extra funding, which is in addition to the local government settlement.
“Under this scenario, teachers would receive a minimum 9% increase between January 2018 and April 2019 and a further 3% rise in April 2020.
“This is a clear indication of our commitment to recruit and retain teachers, and I urge the teaching unions to consider this favourably so that parties can bring discussions to a conclusion.
“I made this proposal to the EIS on Thursday. It is an enhanced offer and I will ask Cosla to agree this and to formally offer it to unions after January 25. I believe this must be put to teachers for their consideration.
“I welcome the agreement by EIS to allow further time to reach an agreement. Industrial action is in no-one’s interests, not least our children and young people. That has been my focus and will continue to be until this is resolved.”
Scottish Greens education spokesman Ross Greer MSP said: “Teachers are overworked, under-resourced and have suffered a 20% real terms pay cut.
“They will continue to have Green support in their campaign for fair pay.”