Montgomery County teachers ratified a new contract Wednesday that would provide raises totaling about 5.5 percent over three years for 12,000 educators but would require employees to pay a larger share of health insurance premiums.

The new compensation, which also includes step increases for eligible employees, is partly offset by the health insurance changes. Identical financial terms have been negotiated with other employee organizations, for a total cost of $35.8 million for new compensation for the school system’s 22,000 employees, school officials said.

For teachers, the new contract also includes provisions for two new initiatives: One would create incentives for high-performing teacher-leaders to work in 57 high-poverty schools. The other is intended to develop ways to add student feedback to the teacher evaluation process, bring teacher feedback into principal evaluations and add principal feedback into associate superintendent evaluations, union officials said.

Salary increases would be 1.5 percent in November 2014; 2 percent in October 2015; and 2 percent in September 2016.

Nearly 94 percent of the 5,516 members who cast votes supported the deal, which would take effect in fiscal year 2015, said Tom Israel, executive director of the Montgomery County Education Association.

Dana Tofig, Montgomery schools spokesman, said a new contract had been approved by the Montgomery County Association of Administrators and Principals (MCAAP). The Service Employees International Union (SEIU) Local 500 is expected to complete its voting process soon, he said.