UChicago Medicine AdventHealth’s four hospitals in Bolingbrook, GlenOaks, Hinsdale and La Grange will be out of network for UnitedHealthcare Medicare Advantage plans on Jan. 1, 2027. UnitedHealthcare says the two sides “made the mutual decision to end” their Medicare Advantage network relationship, which covers individual plans and group retiree plans.
Members of those plans who want to keep using the four hospitals have until Dec. 7, 2026 to pick a different Medicare plan. Anyone who makes no change stays in the same plan, and the hospitals will be outside its network starting New Year’s Day.
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Which plans and hospitals are affected
UnitedHealthcare’s notice, updated Oct. 7, says individual Medicare Advantage plans and group retiree plans are affected. Employer-sponsored and individual commercial plans are not. UChicago Medicine hospitals and providers are already out of network for these plans, so members of these plans have already lost in-network access to the UChicago Medicine side as well.
The hospital’s own Medicare resource hub lists AARP Medicare Advantage plans through UnitedHealthcare and other UnitedHealthcare Medicare Advantage plans, individual and group retiree, as the ones losing in-network access. The hospitals named are Bolingbrook, GlenOaks, Hinsdale and La Grange.
What out-of-network means for a PPO or HMO member
The type of plan decides what happens next. UnitedHealthcare says Medicare Advantage PPO members may see out-of-network providers that participate in Medicare and accept the plan. Group retiree PPO members typically pay the same as they would for in-network care. In both cases, members should confirm with the provider that it will treat them under the plan.
Members in an HMO have less room. The hospital says that when a plan is not in network, non-emergency care will be referred to an in-network provider, and that exceptions may be requested if a service is not available within the plan’s network. In an emergency, UnitedHealthcare says members should go to the nearest hospital, and the visit is covered at the in-network benefit level.
People in active or ongoing treatment for a serious or complex condition at UChicago Medicine AdventHealth may qualify for continuity of care. UnitedHealthcare tells them to call the customer care number on the plan ID card to apply. That request is worth making before Jan. 1, not after a bill arrives.
The enrollment dates that apply
Annual open enrollment runs Oct. 15 through Dec. 7. The hospital’s hub says anyone who does not actively choose a plan will automatically stay in the existing Medicare plan. That means a UnitedHealthcare Medicare Advantage member who does nothing keeps a plan without the four hospitals.
A second window follows. From Jan. 1 through March 31, people already in a Medicare Advantage plan can switch to another Medicare Advantage plan or return to Original Medicare, according to the hub. Drug plans cannot be changed in that window. The window helps a member who finds out in January that a favorite surgeon’s hospital is gone, but it does not undo bills from the first weeks of the year.
Group retiree members get their coverage through a former employer or union, and UnitedHealthcare points them to retiree.uhc.com. Individual plan members, including those in AARP Medicare Advantage plans through UnitedHealthcare, search at myuhcmedicare.com. The January window is for people already in Medicare Advantage, so someone on Original Medicare cannot use it to join a plan.
Members choosing a replacement can call 1-800-MEDICARE (1-800-633-4227) for plan information. UnitedHealthcare also points members to myuhcmedicare.com for individual plans and retiree.uhc.com for group retiree plans to search for in-network providers.
What neither side has said
Neither UnitedHealthcare’s notice nor the hospital’s hub describes a contract dispute or any talks to reverse the change. UnitedHealthcare calls it a mutual decision, so members cannot count on a last-minute deal. Both pages list Jan. 1, 2027 as the date the hospitals leave.
The exit also appears in Medical Economics’ Oct. 29 roundup of Medicare Advantage network breakups for 2027, which lists UCM AdventHealth and UnitedHealthcare’s individual and group retiree plans among Illinois entries and mentions no deal. A hospital that is leaving a network can still treat patients, but the patient’s share of the bill can change.
Doctors matter as much as buildings. A surgeon who operates at one of the four hospitals may still accept a replacement plan, but the plan’s own network decides whether the hospital stay is covered at the in-network level. Calling the plan and asking by hospital name, and then asking the doctor’s office which hospital will be used, answers both halves of the question before Dec. 7.
The practical test for a member is simple: whether a doctor, a surgeon or a hospital the member uses is on the four-hospital list, and whether the replacement plan includes it. Each Medicare Advantage plan keeps its own network, so a plan from another insurer that does include the hospitals has to be confirmed by name before enrolling.
Is a UChicago Medicine AdventHealth hospital on the Jan. 1 list?
A member who waits past Dec. 7 stays in a UnitedHealthcare plan that no longer includes Bolingbrook, GlenOaks, Hinsdale or La Grange, and the first out-of-network bill can arrive before the January switching window helps.
The Medicare Money Bundle gathers eight Medicare guides, including Open Enrollment in an Afternoon: Plan Finder in one sitting, and a keep-or-switch answer. It runs 102 pages with large print, and its Medigap vs. Medicare Advantage guide covers the Medigap rights and state rules that matter when leaving a plan.
This article was produced with AI assistance and edited for accuracy against the sources linked above.
