“Straight Medicare” is an informal term for Original Medicare, the federal health insurance program that includes Part A (hospital coverage) and Part B (medical coverage). It’s called “straight” because it comes directly from the government with no private insurance company in between. You use it as a fee-for-service plan: you see a doctor, Medicare pays its share, and you pay yours.
People typically use this term to distinguish Original Medicare from Medicare Advantage (Part C), which is offered through private insurers. If someone says they’re “on straight Medicare,” they mean they haven’t switched to an Advantage plan.
What Part A and Part B Cover
Part A is hospital insurance. It covers inpatient hospital stays, skilled nursing facility care, hospice care, and home health care. Most people pay $0 in monthly premiums for Part A because they or a spouse paid Medicare taxes for at least 10 years while working.
Part B is medical insurance, covering the outpatient side of health care. This includes doctor visits, lab tests, preventive screenings, mental health services, ambulance services, durable medical equipment like wheelchairs and walkers, and a limited number of outpatient prescription drugs. The standard Part B premium in 2025 is deducted from your Social Security check each month.
Together, these two parts form the core of straight Medicare. They do not include prescription drug coverage, which requires a separate Part D plan.
What Straight Medicare Does Not Cover
Original Medicare has some notable gaps. It does not cover most dental care, including cleanings, fillings, tooth extractions, and dentures. Eye exams for prescription glasses, hearing aids, and hearing aid fitting exams are also excluded. Long-term care, cosmetic surgery, massage therapy, and routine physical exams fall outside its scope as well.
These exclusions are one reason many people on straight Medicare add supplemental coverage or choose a Medicare Advantage plan that bundles some of these benefits.
How Costs Work
Straight Medicare operates on a cost-sharing model. You pay deductibles, copayments, and coinsurance for the services you use, and there is no annual cap on what you can spend out of pocket. That last point is important: unlike most private insurance plans, Original Medicare has no maximum out-of-pocket limit, meaning a serious illness or extended hospital stay can get expensive fast.
For Part A, the inpatient hospital deductible is $1,676 in 2025 per benefit period. The first 60 days of a hospital stay cost nothing beyond that deductible, but days 61 through 90 carry a copayment of $419 per day. If you need to dip into your 60 lifetime reserve days, the copayment jumps to $838 per day. After those reserve days are used up, you pay the full cost yourself. Skilled nursing facility stays cost $209.50 per day for days 21 through 100.
For Part B, you pay a yearly deductible, and after that, you typically owe 20% of the Medicare-approved amount for each service. That 20% coinsurance has no ceiling, which is why supplemental insurance matters.
Filling the Gaps With Medigap
Many people on straight Medicare buy a Medigap policy (also called Medicare Supplement Insurance) from a private insurer. Medigap policies are designed specifically to cover the costs Original Medicare leaves behind: deductibles, copayments, and that uncapped 20% coinsurance under Part B.
When you have both Original Medicare and a Medigap policy, the process is fairly seamless. Medicare pays its share of a covered service first, then your Medigap insurer picks up some or all of the remaining balance, depending on the plan you chose. Medigap is only available to people on straight Medicare. If you switch to Medicare Advantage, you can’t use a Medigap policy.
Adding Prescription Drug Coverage
Straight Medicare does not include broad prescription drug coverage. To get it, you need to enroll in a standalone Part D plan offered by a private insurer. You must have Part A, Part B, or both to be eligible. Part D plans vary in which drugs they cover and what they cost, so comparing options during open enrollment each year is worth the effort.
If you delay enrolling in Part D when you’re first eligible and don’t have other creditable drug coverage, you’ll pay a late enrollment penalty for as long as you have Part D. The penalty increases the longer you go without coverage.
How Straight Medicare Differs From Medicare Advantage
The biggest practical difference is provider access. With straight Medicare, you can see any doctor or visit any hospital in the country that accepts Medicare, with no referrals and no network restrictions. Medicare Advantage plans usually limit you to a network of providers, and going out of network for non-emergency care either costs significantly more or isn’t covered at all.
Prior authorization is another key distinction. Original Medicare rarely requires you to get approval before receiving a service or supply. Medicare Advantage plans frequently require prior authorization, meaning the plan must approve certain treatments or procedures before you receive them.
Medicare Advantage plans often bundle Part D drug coverage and may include extras like dental, vision, and hearing benefits that straight Medicare lacks. They also have annual out-of-pocket maximums, which Original Medicare does not. The tradeoff is less flexibility in choosing providers and more administrative hurdles for certain care.
Who Is Eligible and When to Enroll
Most people become eligible for Medicare when they turn 65. Your Initial Enrollment Period is a seven-month window that starts three months before your 65th birthday month and ends three months after it. If you’re already receiving Social Security benefits, you’ll be enrolled in Part A and Part B automatically. Otherwise, you’ll need to sign up yourself during that window.
People under 65 can also qualify if they have certain disabilities or end-stage renal disease. Once enrolled, you’re on straight Medicare by default. Switching to Medicare Advantage is an active choice you make during designated enrollment periods.