Comparing Medigap policies
Each lettered Medigap policy must by law offer exactly the same benefits, regardless of the insurer that sells it. But insurers still charge widely varied premiums, so it pays to shop around. You can compare policies, and find contact information for the insurers that sell them, by following these steps:

1.  Go to www.medicare.gov

2.  Click on the "Supplements and Other Insurance" tab at the top of the home page, and then select "Find a Medigap Policy" on the drop-down menu.

3.  Enter your ZIP code, ignore the question on health status and check "No" to the question on whether you already have a Medigap policy. Click on "Continue."

4.  You will now see a chart listing each of the different Medigap plans with broad information about them.

5.  To see cost and benefit details of each kind of policy, click on the letter name of each plan.

6.  To see which companies sell any plan, click on the "Companies offering this policy" link at the top of the "details" page for that plan. (Or go back to the main chart and click on the link in the right-hand column for that plan.) To find out the premium you would be charged, you will have to contact the companies by phone or through their websites, using the contact information provided for each company.

7.  This page also tells you each insurer's rating method, which affects the premiums you will be charged.  "Community rating" means that the premium is the same for everybody, regardless of age and cannot increase as you become older.  "Issue age rating" means that the premium is based on your age when you first buy the policy and cannot increase as you grow older.  "Attained age rating" means that the premium increases with every birthday.  (In all these cases, the premiums can go up for other reasons, such as inflation.)

Patricia Barry is a senior editor at the AARP Bulletin.

Updated January 2013