No, you are not required to buy a Medicare prescription drug (Part D) plan from the same insurance company. In many cases, the cheapest Part D plan is from another company and it is a a good idea to look at all plans in a plan at the same time you choose your Medicare coverage.
If you wait, you may have to pay a late penalty for adding Part D later.
With the cost of prescription medications rising faster than the average paycheck, it’s important to think about options that can help. Take time to understand the parts of Medicare so that you can decide the best Medicare options for your needs.