It’s going to be another turbulent sign-up period for Medicare.

Seniors in Medicare Advantage will have fewer choices for coverage next year after insurers — laser-focused on resuscitating flagging margins after years of unexpectedly high medical spending — slashed the number of plans on offer for 2027, according to a Healthcare Dive analysis of new government data.

The highly anticipated landscape file released by the CMS on Monday gives the market its first comprehensive look at how insurers rejigged their MA businesses ahead of the Medicare open enrollment period. Overall, the total number of MA plans nationally is expected to remain relatively flat, sliding slightly from 5,553 in 2026 to 5,532 in 2027. The Trump administration touted “stability” for seniors in a press release.

But that obfuscates significant turmoil under the surface, as major insurers broadly reduced their plans while increasing cost sharing for enrollees in the plans that remain, the data shows. As a result, hundreds of thousands, if not millions, of beneficiaries could see their current plan eliminated by their insurer, be blindsided by the loss of a particular benefit or be forced to manage a significantly higher maximum out-of-pocket cost limit next year.

The situation could be more difficult for beneficiaries who also experienced the atypically volatile sign-up period for 2026. Nearly 3 million seniors had to find new MA coverage after losing access to their old plans this year, according to research from Johns Hopkins.

Comments from insurance executives, along with early hints from brokers — and now, more direct proof in the landscape file — suggest 2027 enrollment will be more of the same, as insurers sacrifice membership for margin improvement for a second year.

Across markets, insurers are offering fewer MA, MA-prescription drug, and standalone prescription drug plans next year, according to Healthcare Dive’s analysis.

Researchers with investment bank Stephens dug into the changes for major insurers, and found that every one pared back the number of individual MA plans it has on offer in 2027. The magnitude of cutbacks ranged from about 3,000 fewer unique plans for Centene to about 150 fewer for Elevance.

UnitedHealthcare, the largest MA insurer, is nixing about 690 plans, while Humana, the second-largest, is culling about 2,400.

Standalone MA and MA-PD cuts are balanced by another year of growth in special needs plans, which cover members with specific long-term health issues, who also qualify for Medicaid or who need institutional care.

SNPs are increasingly popular with insurers as the population ages and their needs become more complex — and because they generate higher per-enrollee margins than other MA plans.

Geographically, most of the major MA insurers are reducing the number of counties served by their traditional MA offerings.

Of the major publicly traded insurers, Centene is again making the most drastic exits, departing 344 counties for 2027, according to Stephens. The managed care giant is trailed by CVS, UnitedHealthcare and Elevance, which are exiting 103, 63 and 56 counties, respectively.

Smaller insurers Devoted Health and Alignment Healthcare are bucking the trend, adding 336 and 9 counties, respectively — as is Humana, which is adding 39 counties for 2027.

Insurers curtailing their plans and market presence doesn’t necessarily translate into lower MA enrollment next year. Insurers could recapture any members they lose from cuts into different plans, if there’s one available in the same market. Small or regional insurers looking to expand could also snap up seniors cut adrift by their larger competitors.

But, “while the exact magnitude remains somewhat unclear, we think this does point to most [MA companies] trimming their footprints and creating disruption in 2027 [enrollment period],” J.P. Morgan analyst Lisa Gill wrote in note Monday.

Overall, MA enrollment is expected to drop to 34 million people next year, down about 2 million people amid the market turmoil, according to insurer projections.

That could mean that MA would account for less than half of total Medicare population for the first time since 2023.

Instability in MA doesn’t bode well for the Trump administration, which is wary about seniors losing benefits — especially during a midterm election year. The CMS attempted to soften the blow in a press release Tuesday, stressing that plan projections historically understate actual enrollment and that coverage options remain robust.

More than 99% of Medicare beneficiaries will have access to at least one MA plan, while 97% will have access to 10 or more options, the CMS said.

Moreover, about 8 in 10 MA seniors will be able to remain in their current plan with the same or a lower premium in 2027.

“The strong 2027 outlook means Medicare beneficiaries will continue to have access to affordable coverage and broad plan choice,” the agency wrote.

The CMS also touted how weighted MA premiums are expected to decline more than 16%, from $14.37 in 2026 to $12.00 in 2027.

However, that calculation includes lower overall premiums for SNP plans, so it underestimates premium changes for the general enrollment MA population, which accounts for the brunt of the program.

Premiums for MA-PD plans are increasing by several dollars on average next year, in part because insurers lowered the number of $0 premium plans on offer, according to a J.P. Morgan analysis of the data.

Overall, insurers are less focused on increasing the monthly cost of coverage than they are on bumping up cost sharing. Seniors may not see a larger upfront bill for insurance next year but will likely have to pay a higher portion of their medical costs when they receive healthcare.

The industry-weighted average premium is staying largely flat next year, up about 1%, according to Whit Mayo, an analyst with Leerink Partners. But the average maximum out-of-pocket limit is up 10% on average, while Part D deductibles are up 30%.

Five-state MA insurer Clover Health increased its cost sharing the most compared to its publicly traded peers, hiking its Part D deductible 192% and its maximum out-of-pocket limit 13%, Mayo wrote in a note Tuesday.

By comparison, UnitedHealthcare increased its maximum out-of-pocket limit 11% and its Part D deductible 33%, while Humana increased its maximum out-of-pocket limit 8% and its Part D deductible 30%. (Though, UnitedHealthcare increased its premiums more than its closest competitor, boosting them 9% to Humana’s 1%.)

The landscape file doesn’t include information on other components of plans’ benefit designs for 2027, like changes to co-pays, drug formularies or the supplemental benefits popular with seniors.

The CMS said it expects supplemental benefits to “remain stable” in the coming year.

But they also appear to be shrinking. Nearly 70% of health plan leaders expect their overall MA benefit packages to be less rich in 2027, including in higher specialist co-pays and reduced dental coverage, according to a survey from HealthScape Advisors.

Dueling narratives, between the stability touted by the CMS and the volatility apparent in the landscape file, could spur confusion about what’s on offer for Medicare seniors, especially those not versed in health literacy.

Seniors find it difficult to digest changes to their coverage even on a normal year. Many seniors find shopping for plans confusing, or plan to reenroll in coverage without reviewing their Medicare plan options, according to insurance marketplace eHealth. As such, many MA enrollees could end up in coverage for 2027 without realizing it may be less generous than it appears.

Medicare open enrollment begins Oct. 15.