Medicare Supplement

How Medigap's Lettered Plans Work in Pearl City

PEARL CITY, Hawaii — If you've ever tried to shop for a Medicare Supplement policy, you've probably run into a wall of letters: Plan A, Plan B, Plan G, Plan N, and more. It looks confusing, but there's actually a simple system behind those letters — and once you understand it, comparing your options gets a lot easier.

Here's a plain-language look at what Medigap does, how the standardized letters work, and what Pearl City residents should keep in mind.

What a Medigap plan actually does

Medigap is short for Medicare Supplement Insurance. It works alongside Original Medicare (Part A and Part B) to help pay some of the costs Medicare doesn't cover on its own — things like coinsurance, copayments, and certain deductibles.

A Medigap policy is sold by a private insurance company, but the benefits inside each lettered plan are set by federal rules. That means a Plan G from one company covers the same basic benefits as a Plan G from another company. The differences show up in price, customer service, and extras — not in what the letter itself covers.

Medigap does not include prescription drug coverage. If you want drug coverage, you'd add a stand-alone Part D plan.

Why the letters exist

Before the standardization rules, Medigap policies varied wildly from one company to the next, and it was almost impossible to compare them fairly. To fix that, the federal government created a set of standardized plans, each identified by a letter.

Today, in most states, Medigap policies are offered as Plans A, B, C, D, F, G, K, L, M, and N. (Massachusetts, Minnesota, and Wisconsin follow their own standardized systems.) Each letter represents a fixed package of benefits. Once you know what a letter covers, you know what every insurer's version of that letter covers.

You can see the official benefit chart on Medicare.gov's Medigap page.

A few important rules about eligibility

Medigap is designed to work with Original Medicare, not with Medicare Advantage. If you're enrolled in a Medicare Advantage plan, you generally can't also use a Medigap policy.

There's also a key timing rule: your Medigap Open Enrollment Period is a 6-month window that starts the month you're 65 or older and enrolled in Part B. During that window, insurers can't turn you down or charge you more because of health problems. Outside that window, in most cases, they can — so this is a period worth paying attention to.

People new to Medicare after January 1, 2020, cannot buy Plans C or F, because those plans covered the Part B deductible and are no longer sold to newly eligible enrollees. If you became eligible before that date, you may still be able to buy them.

How this looks in Pearl City

Pearl City is in Honolulu County, where residents have access to Original Medicare plus the same lettered Medigap plans available across Hawaii. Because Medigap benefits are federally standardized, the letter you choose means the same thing here as it would on the mainland. What can differ locally is which insurers sell which letters, and at what price.

If you're weighing Medigap against a Medicare Advantage plan, that's a separate decision — and one worth thinking through carefully, since switching between the two later can be harder than it sounds.

Where Medigap fits with Part D and 2026 changes

Medigap doesn't cover prescriptions, but the Part D program has some notable 2026 updates worth knowing about:

• The Part D out-of-pocket cap is $2,100 in 2026.
• The Part D maximum deductible is $615.
• The old coverage gap (the "donut hole") was eliminated in 2025, leaving three simpler phases.
• The Medicare Prescription Payment Plan lets you spread your drug costs across the year in monthly amounts instead of paying large sums at the pharmacy counter.
• IRMAA surcharges (higher premiums for higher-income enrollees) start above $109,000 in income for single filers in 2026.

These figures are program-wide and set by CMS — they apply whether you live in Pearl City, Hilo, or anywhere else.

Key dates to remember

• Annual Enrollment Period: October 15 – December 7 (for Part D and Medicare Advantage changes).
• Medicare Advantage Open Enrollment: January 1 – March 31.
• Medigap Open Enrollment: the 6-month window starting the month you turn 65 and are enrolled in Part B.

Medigap isn't tied to the fall Annual Enrollment Period the way Part D and Medicare Advantage are, which surprises a lot of people.