Medicare's open enrollment window is closed, but the bill for millions of retirees is still changing.
The standard Part B premium for 2025 is $185.00 a month, up about $10.30 from last year — roughly a 5.9 percent increase that quietly eats into Social Security checks before they ever hit the bank.
For a program that covers doctor visits, outpatient care, and preventive services, that monthly charge is unavoidable for most enrollees.
Unlike Part A, which is usually free, Part B comes with a price tag that scales with your income — and higher earners pay a lot more than the headline number suggests.
The income brackets are where things get painful.
Single filers earning above $106,000, or couples above $212,000, pay an income-related monthly adjustment amount on top of the base premium.
At the top tier, that surcharge pushes the monthly cost past $600 per person.
The thresholds adjust each year, but not always fast enough to keep pace with inflation or a good year in the market.
There's a detail that trips up a lot of people: your premium is based on your tax return from two years ago.
So a one-time bump in income — a home sale, a Roth conversion, a big capital gain — can raise your Medicare bill even after your finances cool off.
The Social Security Administration does allow you to request a reduction if you've had a qualifying life-changing event, like retirement or marriage, but you have to file the paperwork yourself.
If you're still working and covered by an employer plan, you may be able to delay Part B without penalty — but only if that coverage is considered credible.
Miss the sign-up window and you can face a permanent late enrollment penalty of 10 percent for every 12 months you waited.
That surcharge sticks around for as long as you have Part B.
The timing also matters because Part B premiums are typically deducted straight from Social Security benefits.
That means the annual cost-of-living adjustment can look generous on paper while the actual deposit barely moves.
For retirees on a tight budget, the gap between the headline COLA and the real-world check is often the whole story.
One more thing worth checking: if your income dropped recently, you can appeal the surcharge using form SSA-44.
It's not automatic, and it's not guaranteed, but it's free to try and could save hundreds of dollars a year for those who qualify.
Our take: Part B is one of the few line items in a retiree's budget that's both mandatory and rising faster than many pensions.
Final Thoughts
Reviewing your income tier and your enrollment timing once a year isn't glamorous, but it's one of the most reliable ways to keep more of your Social Security check where it belongs — in your pocket.