Tufts Health Plan is expanding its business in Rhode Island.

The Watertown-based health insurer said Thursday that it has won a five-year contract to manage care for Rhode Island residents on Medicaid. Tufts will be the third company to insure Medicaid members in that state, along with Neighborhood Health Plan of Rhode Island and UnitedHealthcare Community Plan. State officials will pay the insurers monthly to cover health benefits for low-income families and individuals on Medicaid.

Tufts, which has about 1.2 million members, said it hopes initially to enroll about 16,000 Rhode Island residents on Medicaid. The company already sells commercial health insurance plans to 36,000 people in the state. Tufts also sells health insurance in New Hampshire.

Rhode Island health officials said about one-third of the state’s population, or about 300,000 people, are on Medicaid. Rhode Island, like Massachusetts, is working to restructure its Medicaid program. The goal is to provide better and less expensive care by requiring insurers and health care providers to coordinate services for patients. Under the new structure, insurers and providers that fail to stick to certain budgets and meet quality benchmarks will be penalized, while organizations that stay on budget will be rewarded.

“We look forward to working with Governor [Gina] Raimondo and the state to support their efforts to improve Medicaid in Rhode Island,” Tufts chief executive Tom Croswell said in a statement.

Priyanka Dayal McCluskey can be reached at priyanka.mccluskey
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