There are a total of 24 Medicare Part D prescription drug plans available for purchase in the state of Washington. These plans are sold and serviced by 12 different healthcare providers under the direction of the federal government’s Medicare program. In order to qualify for enrollment in one of these plans, you’ll need to be enrolled in Original Medicare Part A and Part B.

You may then apply for your preferred Part D plan in person at the provider company’s office. Some companies may offer online applications via their official website. Whichever application method you choose, you should apply as soon as you’re eligible. Failure to apply in a timely manner could result in penalties, higher monthly costs, and possible health audits.

Medicare Part D vs. Medicare Advantage

You might also consider a Medicare Advantage plan for your prescription drug needs. While Advantage (also called Medicare Part C) is intended to replace Original Medicare Parts A and B, some plans do feature additional prescription drug coverage. You’ll need to shop around your local providers to see if an Advantage plan or a Part D plan is the best fit for your particular needs. Like Part D plans, Advantage plans are sold and serviced by third-party health care providers. Costs and availability will vary, and it’s also worth noting that some Advantage plans are not compatible with Part D plans. This means that if you are enrolled in an Advantage plan and you subsequently enroll in a Part D plan, your Advantage insurance will be canceled and you will revert back to Original Medicare Part A and Part B.

You should always consult with your health plan administrator and your doctor before making any changes to your coverage.

When to sign up

The sign-up process is time-sensitive, so you’ll want to make sure that you take advantage of the Initial Enrollment Period. This period starts three months prior to your Original Medicare eligibility date and ends four months after the same date, which gives you a total of seven months to research Part D plans and complete the application process. Your Original Medicare eligibility date is based on your birth month and your 65th birthday.
If you fail to apply to a Part D plan during the Initial Enrollment Period, you can try again during the Annual Election Period. This period starts on October 15th of each calendar year and concludes on December 7th of the same year. If you can’t apply by this time, you can petition Medicare for inclusion in one of its Special Election Periods. These periods are typically provided to assist people with hardships, so it’s better to apply during one of the earlier periods if at all possible. The longer you wait, the greater your chance of a health audit, late fees, and higher monthly premium costs.

What are my choices?


The Medicare Part D services listed in the preceding table are provided in all Washington counties. Your county of residence may provide additional plans and services. Contact your local Medicare office for additional details.


Plans are subject to change as contracts are finalized.

Includes contracts/plans as of April 22, 2016. The data does not reflect information for employer-sponsored plans, Part B-only plans, or plans not offering a Part D drug benefit.

by Lindsay Malzone, Lindsay Malzone is the Medicare expert for She's been contributing to many well-known publications as an industry expert since 2017. Her passion is educating Medicare beneficiaries on all their supplemental Medicare options so they can make an informed decision on their healthcare coverage.