Mayo Clinic and UnitedHealthcare have reached a contract agreement giving in-network clinic access to seniors with Medicare Advantage coverage from the giant health insurer.

The deal comes about six months after Mayo stopped scheduling appointments for patients with UnitedHealthcare Medicare Advantage coverage due to capacity concerns.

At the time, Minnetonka-based United hadn't negotiated financial terms with Mayo under a network arrangement, which means the insurer was one of several "noncontract" Medicare health plans that, in general, don't pay as much for medical services.

Neither party disclosed financial terms of the new multiyear agreement, which takes effect for Medicare enrollees on Jan. 1 .

"We're expanding and strengthening our longstanding relationship with Mayo Clinic, one of the most highly regarded medical institutions in the world," Craig Stillman, the chief executive of UnitedHealthcare's Medicare business in the Upper Midwest, said in a statement.

UnitedHealthcare said it's the first such contract that gives its Medicare Advantage enrollees from across the nation access to Mayo facilities in the Midwest on an in-network basis. Enrollees typically pay less out-of-pocket when they get care from in-network doctors, clinics and hospitals.

The agreement also means people with coverage through employer groups and individual health plans will continue to have access to Mayo facilities and providers, UnitedHealthcare said in a statement.

"We look forward to building on the continued strong relationship between Mayo Clinic and UnitedHealthcare," Dr. Lyell Jones, a Mayo Clinic neurologist and medical director for contracting and payer relations, said in a statement. "Agreements between Mayo Clinic and leading insurers such as UnitedHealthcare help ensure access for patients who need serious and complex care."

Clinic officials told the Star Tribune in February that between 2019 and 2021, the number of Minnesota patients coming to Mayo with coverage from noncontract Medicare Advantage insurers nearly doubled to more than 3,200 people.

Also during the two-year period, Mayo saw a 42% jump in out-of-state patients coming to Rochester from noncontract Medicare Advantage plans, for a total last year of more than 7,000 people.

The growth was threatening to crowd out patients from health plans where the clinic was an in-network provider, Mayo said at the time. The clinic said UnitedHealthcare enrollees accounted for at least half of the growth from noncontract health plans.

Mayo's policy on scheduling appointments, which it newly began to enforce last winter, means the clinic does "not accept noncontracted Medicare Advantage patients who don't have immediate medical need," a spokesman said Wednesday via e-mail.

The new agreement "allows us to include UHC Medicare Advantage members in our service to those with complex and serious needs," the spokesman said.

UnitedHealthcare has been growing enrollment in Minnesota since 2017 when it announced its goal to become a bigger health plan in its home state. The company gained a foothold in the market when a federal law eliminated Medicare "Cost" health plans in most Minnesota counties in 2019, forcing many seniors to shop for new coverage.

A Star Tribune analysis of federal data shows that UnitedHealthcare's Medicare enrollment in Minnesota grew from about 9,000 people in early 2019 to more than 56,000 people in early 2022.

UnitedHealthcare is seeing growth in other segments of Minnesota's health insurance market as well.

In November, Minnesota's health insurance program for lower-income residents announced it was adding UnitedHealthcare as an option for beneficiaries this year. The decision made United the first for-profit HMO in Minnesota's managed care program for Medical Assistance, the state's name for the state-federal Medicaid program.