Health insurer UCare is telling about 8,400 patients they won't be able to keep visiting their doctors at certain HealthPartners clinics next year unless they switch to a new health plan.

The clinics have been out-of-network for several years at the Minneapolis-based insurer, but UCare has been waiving rules that otherwise would have blocked patients from making appointments.

No more. Now, UCare says it will start enforcing these network rules on Jan. 1, at which point patients will no longer be able to schedule visits at many clinics operated by HealthPartners, the Bloomington-based health system that's one of the largest health care providers in the Twin Cities.

The insurer sent letters about the change dated Nov. 25, but one patient contacted the Minnesota Star Tribune on Monday saying he only just received the notice. The disruption is the latest in a series of network moves this fall that have threatened to impact thousands of Medicare Advantage patients, although the UCare-HealthPartners dispute is the first to spill over into Medicaid health plans where lower-income residents obtain coverage. The changes affect some people eligible for both Medicare and Medicaid.

"Starting on January 1, 2025, you will not be able to schedule appointments or receive care with HealthPartners Clinics and providers as a UCare member," the insurer's letter to patients says. "We want to make you aware and help you prepare for this change."

The change applies to more than 5,000 people in state public health insurance programs for low-income residents that are administered by UCare, including seniors who qualify for both Medicaid and Medicare coverage, often known as "dual eligibles." It also applies to fewer than 3,000 people in Medicare Advantage health plans from UCare.

The health insurer says low-income residents with state-sponsored benefits can contact officials in their county of residence to request a health plan change due to a "good cause" exception.

The initial period for selecting Medicare Advantage plans for 2025 has ended, but seniors in these plans can contact the federal government and request a special enrollment period to change coverage or make a change during the annual Medicare Advantage open enrollment period, which runs Jan. 1 through March 31.

"Although HealthPartners medical group clinics have not been in UCare's network for many years, we have made exceptions and paid for services at these clinics to ensure continuity of care if the member went to a HealthPartners clinic due to confusion," UCare said in a statement to the Minnesota Star Tribune. "We are clarifying HealthPartners' network status for members, in collaboration with HealthPartners, to ensure members can make choices that best meets their needs."

UCare added: "We are committed to helping impacted members work through the change and ensure there is no disruption in their ongoing care."

HealthPartners said in a statement it was notified of the change by UCare late this fall. It applies to primary care, urgent care and specialty care at HealthPartners clinics, as well as nonemergency care at Regions Hospital in the east metro.

"As we have shared with UCare, not having these locations treated as in-network is problematic given the integration of our clinicians and care teams, and referrals that cross our integrated care system," HealthPartners said in a statement.

The change does not apply, however, to many other facilities operated by the health system, which runs a health insurance division that competes with UCare in the market for privately run Medicare and Medicaid plans. UCare subscribers, for example, can still visit on an in-network basis the Park Nicollet clinics and Methodist Hospital in St. Louis Park, all of which are owned by HealthPartners, as well as Lakeview Hospital in Stillwater and HealthPartners Stillwater.

HealthPartners said in its statement: "We'll continue to work with UCare on a transition plan to minimize the disruption as best we can. We will support patients in finding in-network care, whether that's with another part of our organization or with another health plan."

Over the past six months, several Minnesota health care providers including Minneapolis-based Allina Health have announced they'll go out-of-network next year with Medicare Advantage plans from Kentucky-based Humana. Mayo Clinic and M Health Fairview have announced new limits on access for patients in Medicare Advantage plans that don't have network contracts with the health care providers.

HealthPartners and Essentia Health announced earlier this year they'd be going out-of-network with Medicare Advantage plans from Minnetonka-based UnitedHealthcare, but the health systems and insurer ultimately worked out new network agreements that will maintain access in the new year.