(RALEIGH) -- A bill that would overhaul the health insurance plan for state employees, teachers and retirees is headed to the North Carolina House. Senate lawmakers gave final approval to measure.

The half-billion dollar fix would require all state workers and retirees in a more generous plan to pay monthly premiums for the first time ever. Democratic Sen. Doug Berger said the state could face a legal challenge by changing retiree benefits. "The came to work for the state. They put in the years required by us as far as what they had to do to premium free health insurance.  We need to keep that promise and we need to stay out of court," said Berger.
 
Senators rejected a Democratic amendment that would have eliminated the retiree premium. Republican Sen. Jerry Tillman said he understands concerns about the premium increase but the current health plan is unsustainable. "We find ourselves with a plan that is either eventually going to have to be fixed, we've got a good first step here, or we're going to have to drop the plan and say, folks go to the private market and see what you can get for nothing," said Tillman.