BOSTON —Unions were furious Thursday after the Group Insurance Commission voted to restructure its health insurance offerings for state employees and retirees, criticizing the agency for what they considered a rushed vote that could impact hundreds of thousands of residents.

The GIC, which manages health insurance benefits for 400,000 state workers and retirees, finalized a plan that would curtail the number of insurance companies that can sell plans through the agency beginning July 1.

All plans offered by Harvard Pilgrim Health Care and Fallon Community Health were eliminated from the menu, and Tufts Health will only sell plans to Medicare recipients.

UniCare, which is based in Indiana, Neighborhood Health Plan and Health New England will be the only three carriers to offer commercial plans to active state workers and non-Medicare retirees, down from six choices currently.

State officials said the change would save the state $20.8 million next year and make choices easier for beneficiaries by eliminating similar plans with similar benefits. The GIC also said almost half of all members would be able to keep their plans, and most members would be able to keep their doctors and networks, even if they are forced to switch plans.

"GIC officials are telling us that doctor-patient relationships will not be interrupted and overall plan cost increases will be minimized and some out-of-pocket expenses may be reduced. That remains to be seen and we'll be doing our own analysis going forward and hold them accountable to those claims," said Jim Durkin, legislative director for AFSCME Council 93, which represents more than 20,000 GIC members.

Durkin, however, blasted GIC management for the way the vote transpired on Thursday.

According to Durkin and other union officials, members of the GIC commission did not receive their final packets with the details on the final plan they were to vote on the next day until dinnertime the night before.

"They need to change the way they do business," Durkin said. "They need to be respectful of the commissioners and understand when you tell people their insurance provider is not going to be available that makes a significant impact. It was typical with the way they operate, not enough time for thoughtful, careful analysis."

That sentiment was echoed by Massachusetts Teachers Association President Barbara Madeloni.

"I'll be honest, I haven't had a chance to the review the decision that was made, and that is really what is the problem," Madeloni said. "This is no way to run a commission. It's shameful, and it's outrageous."

The vote in favor of GIC's plan consolidation wound up being 8-5, with all five no votes coming from union representatives and two commission members abstaining.

The Group Insurance Commission started the procurement process for insurance carriers in July of last year, and gathered feedback through hearings around the state in October and a member survey. The agency plans another listening tour beginning Friday ahead of votes in February on benefit design and final rates.

"Today's vote stemmed from a yearlong procurement process, which has been widely socialized and shared with our commission throughout," GIC chief of staff Ashley Maagero Lee said.

Peter MacKinnon, president of SEIU Local 509, said a top priority for his union will be to ensure continuity of providers for his membership.

"State employees should have the basic freedom to choose the doctors and networks that are best for their families, yet today, the GIC voted to drastically cut the number of plans available to them. Though we will take the coming days and weeks to closely review the changes, it is already evident that the GIC has taken a bad situation and made it far worse with this anti-consumer vote," MacKinnon said.

The plans excluded from participating in the GIC next fiscal year were also disappointed.

"We are disappointed by the Group Insurance Commission's decision. It has been our honor and privilege to serve the employees and retirees of the state of Massachusetts for many years. The Harvard Pilgrim team will work with the GIC to ensure a smooth transition for the members we have served so proudly while we continue to introduce innovative products, programs and services to grow our business in Massachusetts, Maine, New Hampshire, Connecticut and throughout the country," Harvard Pilgrim said in a statement.

Tufts Health Plan, which will lose about 90,000 members in its GIC commercial plans, said the direct impact to the company is unclear at this time.

"We learned today the GIC voted to consolidate its commercial health plan offerings from six health plans to three. We have a very proud history of serving the GIC since its inception in 1983, and were disappointed to hear this news," the company said in the statement.

Tufts will continue to offer its Medicare Advantage plan as one of two approved Medicare carriers, along with UniCare, and will begin offering a Medicare supplement plan as well. The company, which has sold plans through the GIC since its inception in 1983, said it has about 13,000 Medicare members through the GIC now.

"We are extremely proud of the work we have achieved during the course of our more than 30-year history. We also feel that our response in the GIC's procurement process was extremely strong," Tufts statement said.