Medicare Part A and Part B: What Each Covers

Part A and Part B cover different kinds of care. Part A is hospital insurance. Part B is medical insurance. Together they form Original Medicare. Having both does not mean every service is covered or that every bill is paid in full.

Start with the type of service

An overnight hospital stay is not always inpatient care

Ask whether you have been formally admitted as an inpatient or are receiving outpatient observation services. The distinction can affect your bills and eligibility for subsequent skilled nursing coverage. An emergency department visit or a bed in a hospital does not, by itself, establish inpatient status.

Keep the different costs separate

A premium keeps coverage in place. A deductible is an amount you may need to pay before certain coverage begins. Coinsurance or a copayment is your share of a covered service. Part A and Part B have different cost rules; Original Medicare does not have an annual limit on your out-of-pocket costs unless you have other coverage that helps.

• Check the effective dates on your Medicare card.
• Ask the provider which part will be billed and whether assignment is accepted.
• Request a written estimate and ask whether separate professionals will send bills.
• If you have other insurance, confirm which coverage pays first.

If you have Medicare Advantage

You still have Medicare, but receive your Part A and Part B benefits through the plan. Check its network, referral, authorization and cost-sharing rules. This overview addresses hospital and medical benefits; it is not a complete inventory of every coverage choice.

Continue with a related question

• Original Medicare or Medicare Advantage: Medical Benefits
• Medicare Premiums, Deductibles and Medical Cost Sharing
• Turning 65: A Practical Medicare Enrollment Checklist

Official information

• Medicare.gov — Parts of Medicare
• Medicare.gov — Inpatient or outpatient hospital status