Every Insurer’s Medigap Plan G Covers the Same Benefits. The Premium Isn’t and on Most Policies It Climbs Every Birthday.

Medigap Plan G premiums for the same 66-year-old can range from $118 to $214 monthly despite identical benefits across all insurers.

Attained-age policies appear cheapest upfront but build birthday-based increases into the rate, potentially making them the most expensive option over time.

Federal law guarantees only one 6-month Medigap switching window at 65; afterward, insurers can deny coverage or charge more based on health.

A 66-year-old Ohio woman pulls three quotes for Medigap Plan G. One costs $118 a month. Another is $167. The highest comes in at $214. The benefits are the same.

That is one of Medigap's stranger features. In most states, lettered plans are standardized, so every standard Plan G covers the same basic benefits regardless of which insurer's name appears on the card. What can vary dramatically is the premium and, just as important, how that premium is priced as she gets older. She picks the $118 policy and congratulates herself on saving more than $1,100 a year. The question she did not ask is what happens to that rate at 70, 75 and 80.

Medicare recognizes three ways insurers can price Medigap policies: community-rated, issue-age-rated and attained-age-rated. A community-rated policy generally charges the same premium regardless of age. An issue-age policy bases the rate on how old the buyer is when the policy is purchased, so later birthdays do not create age-based increases. Neither structure freezes the premium; rates can still rise for inflation, medical costs and other permitted factors.

Attained-age works differently. The premium is based on the policyholder's current age, so it can increase as she gets older, in addition to whatever broader rate increases the insurer receives approval to impose. That makes the cheapest quote today an incomplete comparison.

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The Age Curve Can Hide Behind a Great Introductory Price