Do you have to pay the medicare deductible if they are paying secondary to a primary insurance carrier?

This is directly from the Medicare and You 2009 Book: When you have other insurance, there are rules that decide whether Medicare or your other insurance pays first. The insurance that pays first is called the "primary payer" and pays up to the limits of its coverage. The one that pays second, called the "secondary payer," only pays if it covers any of the costs left uncovered by the primary coverage. If you have other insurance, tell your doctor, hospital, and pharmacy so your bills get paid correctly. If you have questions about who pays first, or you need to update your other insurance information, call Medicare's Coordination of Benefits Contractor at 1-800-999-1118. TTY users should call 1-800-318-8782. You can view the details here: http://www.medicare.gov/Publications/Pubs/pdf/10050.pdf