What do I do if Medicare and BCBS Supplemental both won't pay my screening for mammogram?

If you are over age 65, Medicare is primary unless your BCBS plan (you describe it as "supplemental") is covering you as either an active employee of a company or the spouse of an active employee.

Take this up with your Medicare insurer. Ask them what makes them think they are not primary? They are probably misinformed, but I don't know much about your "supplemental" policy and maybe they do.

Medicare has limitations on how often it will cover a mammogram. See the Medicare website. A supplemental plan won't pay ANYTHING until the primary plan (Medicare) has paid. If your BCBS is supplemental and Medicare says it isn't, then use the claim appeal procedures.

Supplemental plans are NEVER primary. And Medicare will have a deductible. You probably didn't make it clear to Medicare that the other plan was only a supplemental plan; but you'll still have to pay your deductible.

Keep in mind, not ALL parts of Medicare, will pay for this.

Medicare covers a mammogram every 2 years.

Pay it your self!

you pay for it with cash