The agreement would include retroactive pay equivalent to roughly 8 percent of salaries, annual raises of up to 2 percent a year and substantial savings for the city on health coverage, according to one official involved in the talks.
Three officials who insisted on anonymity because the deal had not been made final or announced said it could be disclosed at City Hall on Thursday; one official said the two sides would announce a nine-year contract.
Mr. de Blasio has cleared his schedule for the day, a mayoral spokesman said, postponing a long-planned major announcement about his affordable-housing plan.
One teachers’ union official said: “We’re just finalizing the language. It could be very soon.”
But officials warned that there could be last-minute snags because other municipal unions were weighing in with complaints that the raises given the teachers — which will probably set a pattern for the other unions — were too small and should be higher. Those pressures could cause some changes of the terms of the teachers’ deal.