Medicare Part D 2027: Costs, Coverage, and How to Compare Plans

Medicare Part D 2027 snapshot

Part D covers brand-name and generic prescription drugs, subject to each plan’s drug list and coverage rules. Medicare requires plans to cover a broad range of medications, but a plan does not have to cover every prescription on the market. Every formulary includes at least two drugs in the most commonly prescribed categories and classes, and plans must include most medications in six protected classes: cancer drugs, HIV/AIDS drugs, antidepressants, antipsychotics, anticonvulsants, and immunosuppressants used for organ transplants.

Those protections are important, but they do not eliminate the need to check a specific drug. A medication may appear on a higher-cost tier or require prior authorization, step therapy, or a quantity limit. If a formulary drug or coverage rule does not meet a medically necessary need, the enrollee and prescriber may request a coverage determination or exception. The plan’s Evidence of Coverage and formulary explain how those requests work.

2027 Part D costs and the $2,400 out-of-pocket threshold

Your Part D spending can include a monthly premium, deductible, copayments, and coinsurance. Higher-income beneficiaries may also owe a Part D income-related monthly adjustment amount, paid separately to Medicare rather than to the plan. A late enrollment penalty may be added when a person goes without Part D or other creditable prescription coverage for too long after becoming eligible.

The 2027 national base beneficiary premium is $41.33. This is not a universal plan price. Medicare uses it as a starting point in the formula for plan-specific basic premiums and in late enrollment penalty calculations. The amount shown by an actual plan may be lower or higher based on its approved bid, supplemental coverage, geographic factors, Medicare Advantage rebate treatment, Extra Help, a late penalty, or an income-related adjustment.

The defined-standard deductible

The defined-standard Part D deductible is $700 in 2027. Plans can offer a deductible below that amount, and some plans apply no deductible to selected lower drug tiers. Never assume “$700 deductible” means every enrollee must personally pay exactly $700 before any drug receives plan cost sharing. Read the deductible column for each medication in the plan comparison and verify whether the drug’s tier is exempt.

Initial coverage and catastrophic coverage

Under the defined standard benefit, the enrollee generally pays 25% coinsurance for covered drugs after the deductible during the initial coverage phase. Many plans use actuarially equivalent tiered copayments or coinsurance instead, so the amount at the pharmacy can look different. Once the enrollee reaches the $2,400 annual out-of-pocket threshold for covered Part D drugs in 2027, the catastrophic phase begins and the enrollee has no further copayment or coinsurance for covered Part D drugs for the remainder of the calendar year.

The threshold is not a cap on every health or medication expense. Monthly plan premiums do not count toward it. Drugs excluded from Part D, medications obtained outside the plan’s coverage rules, and purchases that do not qualify as true out-of-pocket spending may not count. Medical cost sharing under Parts A and B or a Medicare Advantage plan is also separate. Use the plan’s records and Explanation of Benefits to track what has been credited toward the Part D threshold.

Insulin and recommended adult vaccines

For a Part D-covered insulin product, the enrollee generally pays no more than $35 for a one-month supply, and the Part D deductible does not apply to that insulin. Covered adult vaccines recommended by the Advisory Committee on Immunization Practices are available without Part D cost sharing when Part D coverage rules are met. The precise product, prescription, and administration circumstances still need to be confirmed.

How to compare 2027 Medicare Part D plans

A dependable Part D comparison uses personal prescription data. A general list of “good plans” cannot show which option best fits a particular person because medication use and pharmacy contracts drive much of the result. Collect the information below before opening Medicare Plan Compare or requesting licensed assistance.

1. Build an exact medication list. Record each prescription’s full name, strength, dosage form, quantity, and refill frequency. Identify brand-name products that cannot be substituted and drugs taken only seasonally or as needed.
2. Choose realistic pharmacies. Include the retail pharmacies you are willing to use and consider mail order when appropriate. Compare preferred-network and standard-network pricing; both may be in network but produce different cost estimates.
3. Check every formulary result. Look beyond “covered.” Note the assigned tier, whether the deductible applies, and whether the plan requires prior authorization, step therapy, or quantity limits.
4. Compare the full-year projection. Review monthly premiums and projected prescription costs together. Pay attention to expensive refill months and not only the annual total, especially if cash flow is a concern.
5. Confirm the coverage route. A standalone plan generally accompanies Original Medicare. Most people cannot pair a separate Prescription Drug Plan with a Medicare Advantage plan that already includes drug coverage, and joining one can cause disenrollment from certain Medicare Advantage coverage.
6. Read the official documents before enrolling. Verify the Summary of Benefits, Evidence of Coverage, formulary, pharmacy directory, star-rating information when available, and enrollment confirmation. Official plan documents control if a summary or comparison differs.

The following table turns those steps into a practical review. It is especially useful when two plans have similar premiums but different rules or pharmacy arrangements.

When you can enroll and how the late penalty works

People commonly enroll in Part D when first eligible for Medicare. The Initial Enrollment Period generally lasts seven months: the three months before the month a person turns 65, the birthday month, and the three months after. Different timing can apply to Medicare eligibility based on disability, End-Stage Renal Disease, or amyotrophic lateral sclerosis, and the effective date depends on when enrollment occurs.

Medicare’s Annual Open Enrollment Period runs from October 15 through December 7 each year. During the 2026 fall period, beneficiaries can review options and make eligible changes for coverage beginning January 1, 2027. Some people qualify for a Special Enrollment Period after events such as losing creditable prescription coverage, moving outside a plan’s service area, entering or leaving an institution, or changes involving Medicaid or Extra Help. Each Special Enrollment Period has its own conditions and deadline.

Medicare Advantage Open Enrollment, January 1 through March 31, is narrower. It is for people already enrolled in Medicare Advantage. An eligible member may generally make one change to another Medicare Advantage plan or return to Original Medicare and, when applicable, join a standalone Part D plan. It is not a general standalone Part D shopping period for everyone with Original Medicare.

Creditable coverage and the Part D late enrollment penalty

Part D is optional, but a penalty can apply if you go 63 consecutive days or more without Part D or other creditable prescription drug coverage after your eligible enrollment period. “Creditable” means the coverage is expected to pay, on average, at least as much as Medicare’s standard prescription drug coverage. Employer, union, Veterans Affairs, TRICARE, and other drug coverage should not be assumed creditable without reviewing the annual notice or confirming with the program.

The penalty is generally calculated as 1% of the national base beneficiary premium multiplied by the number of full uncovered months, rounded to the nearest ten cents. The amount can change when the base beneficiary premium changes, and it is commonly added to the monthly Part D premium for as long as the person has Part D. People who qualify for Extra Help do not pay the Part D late enrollment penalty while eligible.

Keep copies of creditable coverage notices and proof showing when prior drug coverage began and ended. If Medicare or a plan assesses a penalty you believe is incorrect, follow the reconsideration instructions in the notice and provide supporting evidence by the stated deadline.

Budgeting with the Medicare Prescription Payment Plan and Extra Help

Medicare Prescription Payment Plan

The Medicare Prescription Payment Plan is a voluntary option available through Medicare drug plans. It allows an enrollee to spread eligible out-of-pocket Part D drug costs across monthly bills during the calendar year instead of paying the full amount at the pharmacy. The pharmacy does not collect the applicable out-of-pocket amount at pickup; the plan sends bills based on the program’s calculation.

This option changes payment timing, not the total amount owed for covered drugs. It is not a discount and does not reduce premiums or plan cost sharing. It may be useful when significant prescription costs occur early in the year, but joining late in the year can leave fewer months over which to spread the balance. Review the plan’s explanation, billing schedule, payment methods, and consequences of missed payments before participating.

Extra Help with Part D costs

Extra Help, also called the Part D Low-Income Subsidy, can reduce premiums, deductible exposure, and prescription cost sharing for people who qualify. Some beneficiaries receive it automatically because they have Medicaid, receive help from a Medicare Savings Program, or receive Supplemental Security Income. Others may apply through Social Security.

Income and resource standards can change, and certain resources or assistance may be treated differently. Do not rule yourself out based on an older limit or a rough estimate. Check current eligibility information with Social Security, Medicare, or your state Medicaid office. Also review whether the selected plan’s premium is fully covered by the subsidy amount in your region; Extra Help does not make every available plan premium-free.

People with Extra Help may have additional opportunities to change prescription coverage, but permitted frequency and timing depend on current Medicare rules and individual status. Confirm the applicable Special Enrollment Period before submitting a change.

Medicare Part D 2027 frequently asked questions

Related Medicare planning resources

Important Medicare and availability disclosures