What happens if I sign up for Medicare late?

For Part B and Part D, yes. Once the LEP is added to your premium, it stays added for as long as you have that coverage. The Part A LEP is shorter — it's 10% of the Part A premium for twice the number of years you were late. But Part A LEP only applies to the small group that has to BUY Part A (people without 40 work credits). For the vast majority of people, Part A is premium-free and there's no Part A LEP at all.

Count the full 12-month periods you could have had Part B but didn't — starting at the end of your Initial Enrollment Period (or the end of your SEP if applicable). Multiply by 10%. Add that percentage to the standard Part B premium. Example: late by 4 full years means 40% added to the 2026 standard premium of $202.90 — about $81/month extra, every month, for life. The base premium changes annually, so the dollar penalty changes too, but the percentage is locked.

Count the months you went without creditable drug coverage after your IEP ended (more than 63 days at a time). Multiply that number by 1% of the national base beneficiary premium ($38.99/mo in 2026). Round to the nearest 10 cents. That's added to whatever Part D plan you eventually pick. Example: 30 months late = 30% × $38.99 = $11.70/month. Permanent.

For Part B late-enrollment purposes, NO. Only active-employment employer coverage from a 20+ employee employer counts. For Part D, COBRA only counts if the COBRA drug coverage itself is creditable (the plan must send you an annual Notice of Creditable Coverage). This is the most common late-enrollment trap I see — people delay Part B because they're on COBRA, then get hit with the LEP when they finally enroll.

Yes — but the bar is high. For Part B, you can request a reconsideration with SSA on Form SSA-561 (Request for Reconsideration). The strongest argument is 'equitable relief' — SSA gave you wrong information, a federal employee misled you, or there was a federal coverage error. For Part D, the appeal goes to the Independent Review Entity (IRE) administered by C2C Innovative Solutions, with a 60-day filing window. Bring documentation — written notices, plan letters, anything that supports your story.

If you've had continuous creditable drug coverage (whether through MA-PD or stand-alone Part D), no LEP gets added when you switch. But if there's a 63+ day gap in creditable drug coverage during the switch, the LEP starts running. Don't drop one drug plan before another is set up.

Yes. The Part D LEP doesn't apply for any month you're enrolled in the Low-Income Subsidy (Extra Help). Apply through SSA at ssa.gov/medicare/part-d-extra-help or call 1-800-772-1213. The income limit is now 150% of the federal poverty level (expanded by the Inflation Reduction Act, effective 2024). Asset limits also rose.

It depends. Living outside the U.S. doesn't pause the LEP clock by itself. But if you had insurance abroad that was equivalent to Medicare (e.g., national health systems in some countries), you may have an equitable-relief argument. The cleaner path is to enroll during your 8-month SEP that opens when you return to the U.S. and to document continuous foreign coverage. Bring documentation when you talk to SSA.

The GEP is January 1–March 31 each year. It's the catch-up window for people who missed their IEP and don't have an SEP. You can enroll in Part A and/or Part B during the GEP. Coverage starts the month after enrollment (this changed in 2023 under the Consolidated Appropriations Act). The LEP still applies, but the bleeding stops because you're now enrolled.

No — LEPs apply regardless of whether you go with Original Medicare or Medicare Advantage. To enroll in any Medicare Advantage plan, you have to be enrolled in Part A and Part B first. The LEP attaches to your Part B premium and follows you into the MA plan. Switching coverage type doesn't reset the penalty.