Medicare Billing Walkthrough

What actually happens after you see a doctor? The billing process looks very different depending on whether you have Medicare Advantage or Original Medicare with a Supplement. Here's how each works, step by step.

🔵 Medicare Advantage (MAPD)

Your private plan handles everything — Medicare pays the plan a monthly amount; the plan pays your providers.

You see a provider

Must be in-network for most MAPD plans (HMO) or preferred (PPO). Out-of-network care may cost more or not be covered at all.

Provider bills the MAPD plan

The claim goes directly to your private insurance company, not to Medicare. Medicare's role ends here — it pays the plan a monthly capitation amount.

Plan reviews and adjudicates the claim

The plan determines what's covered based on its own rules, formulary, and prior authorization requirements. It may deny claims that Original Medicare would have covered.

You pay your share

Copay (e.g., $20 primary care, $50 specialist) or coinsurance at the time of service or via bill. Costs vary by plan and service type.

Plan pays provider the remainder

After you've paid your share, the plan pays the provider. Your costs accumulate toward the plan's annual out-of-pocket maximum (MOOP).

Key takeaway

One payer, one claim. Your MAPD plan handles everything. Simpler process — but the plan controls what's covered.

🛡️ Original Medicare + Supplement

Two payers work together. Medicare processes the claim first; your Supplement pays the remainder.

You see any provider

Any doctor or hospital in the US that accepts Medicare — no network, no referrals needed. You can go directly to specialists nationwide.

Provider bills Medicare first

The claim goes to Medicare (the federal government). Medicare applies its approved amount and determines what it will pay.

Medicare pays its 80%

For Part B services, Medicare pays 80% of the Medicare-approved amount after the annual deductible is met. For Part A (inpatient), Medicare pays after the per-benefit-period deductible.

Claim crosses over to your Supplement

Most Medigap carriers participate in Medicare's "crossover" system — the claim is forwarded automatically to your Supplement insurer. You usually don't file anything yourself.

Supplement pays your remainder

Depending on your Medigap policy, the Supplement covers the 20% coinsurance, deductibles, and/or copays. With a comprehensive Medigap plan, you often owe $0 at the time of service.

Key takeaway

Two payers, but usually seamless. More flexibility and predictability — but higher monthly premiums than most MAPD plans.

What About Prescription Drugs?

MAPD Plan

Drug coverage is built in. You show your MAPD plan card at the pharmacy. The plan applies your tier copay or coinsurance. Costs accumulate toward your plan's drug MOOP and count toward your Part D out-of-pocket cap ($2,100 in 2026).

Original Medicare + Part D Plan

Your standalone Part D plan is separate from your Medigap. You show your Part D plan card at the pharmacy. The Part D plan applies its formulary tiers. Drug costs do not cross over to Medicare or Medigap — Part D is entirely its own coverage with its own deductible and MOOP.

Common Billing Questions

Will I get a bill every time I see a doctor?

With a comprehensive Medigap plan, often no — the claim is processed automatically between Medicare and your Supplement. With MAPD, you typically pay a copay at the time of service and may receive a bill if coinsurance applies.

What if my MAPD claim is denied?

You have the right to appeal any denied claim. MAPD plans must follow Medicare's appeals process: redetermination by the plan → reconsideration by an independent review entity → administrative law judge hearing → further levels if needed. You have 60 days from the denial notice to start an appeal.

How do I know Medicare paid correctly?

Review your Medicare Summary Notice (MSN), which Medicare sends every 3 months, or log in to Medicare.gov to see your claims. Check that services listed match appointments you actually had and amounts look correct.

What is "balance billing"?

Most doctors who accept Medicare agree to accept Medicare's approved amount as payment in full. Providers who "opt out" of Medicare entirely can charge more than Medicare's rate — this is rare but something to verify before seeing a new specialist.

Questions About Your Medicare Bills?

We can help you understand an EOB, review a bill that doesn't look right, or compare how billing would work under different plan types.

Talk to an Agent