Medicare 2026

Medicare Part B and D Penalties: How Boise Can Avoid Them

Boise, Idaho — For many people turning 65, the trickiest part of Medicare isn't picking coverage. It's the calendar. Miss a key sign-up window for Part B or Part D, and you can end up paying a late-enrollment penalty every month — often for the rest of your life.

Here's how those penalties work, who they hit, and the simple steps Boise-area residents can take to sidestep them.

Why the penalties exist

Medicare is built on the idea that healthy and sick people join together, which keeps costs steadier for everyone. To discourage people from waiting to sign up until they're sick, Congress attached late-enrollment penalties to Part B (doctor and outpatient care) and Part D (prescription drugs).

The penalties are not one-time fees. In most cases they are added to your monthly premium and stay there for as long as you have that coverage.

How the Part B penalty works

The Part B late-enrollment penalty adds 10% to your standard Part B premium for each full 12-month period you were eligible for Part B but didn't sign up.

So if you waited three full years to enroll, your premium would be 30% higher — and generally stay that way for life. You also can typically only sign up during the General Enrollment Period (Jan. 1 – March 31), with coverage starting the month after you enroll.

There is an important exception. If you (or your spouse) were still working and had health coverage through that job when you first became eligible, you likely qualify for a Special Enrollment Period. That lets you sign up for Part B without a penalty, usually within 8 months of losing the job-based coverage.

How the Part D penalty works

The Part D penalty is calculated a little differently. Medicare takes 1% of the "national base beneficiary premium" and multiplies it by the number of full months you went without Part D or other "creditable" drug coverage after you were first eligible.

"Creditable" means the drug coverage is expected to pay, on average, at least as much as standard Part D. Coverage from a current or former employer, union, or the VA often qualifies — but you should get that in writing. Insurers and employers are required to send you a creditable coverage notice each year. Keep it.

The resulting amount is rounded to the nearest 10 cents and added to your Part D premium every month, for as long as you have Part D coverage.

What's changing in 2027

Even if a penalty applies, Part D itself is getting friendlier. The out-of-pocket cap on covered drugs is $2,100 in 2026 and $2,400 in 2027, and the maximum Part D deductible is $615 in 2026 and $700 in 2027. The old "donut hole" coverage gap was eliminated in 2025, leaving three simpler payment phases.

Medicare also offers the Medicare Prescription Payment Plan, an optional program that lets you spread your drug costs across the year in monthly installments instead of paying large amounts at the pharmacy counter.

Higher earners should also be aware of IRMAA, an income-related surcharge that begins above $109,000 for a single filer in 2026 and is added on top of Part B and Part D premiums.

How Boise residents can avoid a penalty

Boise is in Ada County, where — as in the rest of Idaho — beneficiaries have several Medicare Advantage and stand-alone Part D options during Annual Enrollment. But the plan you choose matters less than making sure you enroll on time in the first place.

A few practical steps:

• Mark your Initial Enrollment Period. It's the 7 months around your 65th birthday: the 3 months before, your birthday month, and the 3 months after.
• Don't skip Part D just because you don't take drugs today. Going without creditable coverage is what triggers the Part D penalty later.
• Keep your creditable coverage notices. If you had employer or VA drug coverage, those letters are your proof.
• Use the annual windows. The Annual Enrollment Period is Oct. 15 – Dec. 7. Medicare Advantage Open Enrollment runs Jan. 1 – March 31 for people already in an Advantage plan.
• Ask for free local help. Idaho's State Health Insurance Assistance Program (SHIP), called Senior Health Insurance Benefits Advisors (SHIBA), offers free one-on-one counseling.