Medicare Part D: Complete Guide to Medicare Prescription Drug Coverage

Medicare Part D is prescription drug coverage available to everyone who has Medicare. Part D is offered by insurance companies either as standalone coverage or through a Medicare Advantage Plan.



Each prescription drug plan is different in the drugs that it covers and the amount you have to pay for coverage. Medicare Part D helps offset the cost of prescription drugs, which can be expensive during the senior years.


Video: Understanding Medicare Part D Prescription Drug Coverage


How to Enroll in Medicare Part D Prescription Drug Coverage

To enroll in a Medicare Prescription Drug Plan (separate from a Medicare Advantage Plan), you should have Medicare Part A or Part B (or both).  To enroll in a Medicare Advantage Plan you must have both Part A and Part B. Medicare plans have service areas. You must reside in the service area of the plan you want to join.

You can enroll in prescription drug plan when you are first eligible for Medicare, that is, from three months before your 65th birthday to 3 months after your 65th birthday. Or, if you receive Medicare because of a disability, you can enroll 3 months before your 25th month of disability and 3 months after your 25th month of disability.

If you miss your initial enrollment period, you can also enroll in a prescription drug plan between November 15 and December 31 each year. If you don’t enroll in a prescription drug plan when you are first eligible, you face a late enrollment penalty which results in higher premiums.

The Medicare website has a tool for finding prescription drug plans. You can search for plans even if you are not already enrolled in Medicare.


medicare part D

How Much Does Part D Cost?

Coverage cost for each plan varies. Here are some typical costs you’ll pay for a prescription drug plan.


Monthly premium in addition to the Part B premium. If you have a Medicare Advantage Plan, your premium might include the cost of prescription drug coverage.


Annual deductible that you must pay for prescriptions before your plan starts to pay. Not all plans have a deductible.

Co-payments are the amount you pay for your prescription after the plan pays its share. Co-payments begin after the annual deductible has been met.


Coverage gap. Many plans have a gap coverage that begins after you and your plan have spent a certain amount of money on drugs. In the coverage gap, you must pay the full price of any prescription drugs you receive.


Catastrophic coverage kicks in after you have reached your plan’s out-of-pocket limit for the year.


Video: Enrolling for Medicare Part D


Help Paying For Prescription Drugs

If you have trouble paying for your prescription drugs, you can get a low-income subsidy, also known as “extra help.” To qualify, you should meet the following requirements:


medicare part dYou are single and your income is less than $15,600 and resources (money in checking and savings accounts) is less than $11,990.


You are married, living with your spouse, have no other dependents, your income is less than $21,000, and your resources are less than $23,970.


You can receive help paying your premium, annual deductible, and co-payments. “Extra help” may remove the coverage gap eliminating the risk that you will pay out-of-pocket for your premiums. You can apply for “extra help” by calling Social Security at 1-800-772-1213. You can also apply online at Finally, you can apply with your State Medical Assistance office. Call Medicare at 1-800-633-4227 to get the number.