Whatever you do don't get stuck waiting in line at your local Social Security office to replace a Medicare card that has been lost, stolen, or destroyed. Take care of this online in one of two ways. First, you can go to MyMedicare.gov and request a replacement online. If you don't have an account with MyMedicare.gov, you can sign-up. Second, you can ask for a replacement by using your online my Social Security account. Again, if don’t already have an account, you can create one online. Go to Sign In or Create an Account. Once you are logged in to your my Social Security account follow these 2 steps:
It takes about 30 days to receive your new Medicare card.