Medicare Supplement

Does Plan C or F apply to you in Des Moines?

Des Moines shoppers turning 65 this year have a wide field of Medigap policies to sort through — and a set of federal rules that quietly narrows the list before they start. Medigap, also called Medicare Supplement Insurance, is standardized: every "Plan G" pays the same core benefits no matter whose name is on the envelope. What changes is who sells it, how they price it, and which letters are still open to newly eligible enrollees.

Des Moines is in Polk County, and a Medicare.gov search for ZIP 50309 turned up 29 insurers offering Plans A, B, C, D, F, F-HD, G, G-HD, K, L, M and N in the area. The table below lists every carrier and the letters each one files in Iowa.

What Medigap does — and what it doesn't

Medigap sits next to Original Medicare and helps pay the out-of-pocket amounts Parts A and B leave behind: coinsurance, copays, and (depending on the letter) some deductibles. It does not replace Medicare, and it is not the same as Medicare Advantage. You can't have both a Medigap policy and a Medicare Advantage plan at the same time.

Medigap also does not cover prescription drugs. If you want drug coverage, you'll enroll separately in a Medicare Part D plan. For 2026, Part D has a $2,100 annual out-of-pocket cap and a maximum deductible of $615. The old coverage gap ("donut hole") is gone as of 2025 — Part D now runs in three phases. If drug costs land unevenly during the year, the Medicare Prescription Payment Plan lets you spread them across monthly bills.

The plan letters newly eligible Iowans can buy

Federal law standardizes Medigap into lettered plans. For people who became eligible for Medicare on or after January 1, 2020, the choices are:

• Plan A
• Plan B
• Plan D
• Plan G (and the high-deductible version, G-HD)
• Plan K
• Plan L
• Plan M
• Plan N

Plans C and F remain available only to people who were eligible for Medicare before January 1, 2020. That cutoff exists because those plans covered the Part B deductible, and Congress closed them to newer enrollees.

Iowa follows the federal standard — Massachusetts, Minnesota and Wisconsin are the three states that standardize Medigap differently.

Who sells Medigap in the Des Moines area

The Medicare.gov Medigap policy search returned 29 insurers for ZIP 50309. Some, like Wellmark Blue Cross and Blue Shield of Iowa, are local names Iowans know well; others, such as AARP - UnitedHealthcare Insurance Company, Aetna Health Insurance Company, Humana (Humana Insurance Company), Mutual of Omaha (United of Omaha Life Insurance) and State Farm Mutual Automobile Insurance Company, are national carriers. Not every insurer files every letter — for example, AFLAC files Plans A, F, G and N, while United American Insurance Company files a longer list including A, B, C, D, F, F-HD, G, G-HD, K, L and N.

The full carrier-by-letter roster is in the table below. Because every Plan G is the same Plan G by law, the comparison shopping happens on price and service, not on the benefits inside the letter.

Your best window to buy: the Medigap Open Enrollment Period

The single most important Medigap rule is timing. Your Medigap Open Enrollment Period is the six months that begin the month you are 65 or older and enrolled in Part B. During that window, insurers must sell you any Medigap policy they offer, at the same price as a healthy applicant, regardless of your health history.

Outside that window, in most cases, insurers in Iowa can use medical underwriting — meaning they can ask health questions and decide whether to offer coverage and at what rate. There are federal "guaranteed issue" rights that protect you in specific situations (for example, if a Medicare Advantage plan leaves your area or you move out of its service area). For questions about Iowa-specific consumer protections beyond federal law, the Iowa Insurance Division and Iowa's SHIIP (the state's SHIP counseling program) are the authoritative sources.

How Medigap pairs with Part D

Because Medigap doesn't include drugs, most Des Moines enrollees carry three pieces:

1. Original Medicare (Parts A and B) 2. A Medigap policy 3. A stand-alone Medicare Part D drug plan

You can enroll in or change Part D during the Annual Enrollment Period, October 15 through December 7. That window does not by itself open new Medigap rights — Medigap has its own enrollment rules — but it is when Part D pieces click into place for the coming year.

One note on income: Part D and Part B premiums include IRMAA surcharges when income crosses certain thresholds. For a single filer in 2026, IRMAA begins above $109,000.

Where to get personalized help

Medigap is a long-term decision, and the "right" letter depends on your health, your budget, whether you travel, and how much predictability you want in your monthly costs. Two free, unbiased places to start:

• Medicare.gov — including the Medigap policy search
• 1-800-MEDICARE (24/7)
• SHIIP, Iowa's State Health Insurance Assistance Program, offers free one-on-one counseling from trained volunteers

For questions about a specific insurer's practices in Iowa, the Iowa Insurance Division is the regulator.