How long can a hospital wait to bill you?

A hospital bill can show up months after your care, sometimes more than a year later. This guide explains the time limits that apply, what a late bill can mean, and what to check before you pay. It's part of our guide on how to read a medical bill.

The short version: there's no single federal deadline for a hospital to bill you directly. But there are deadlines for billing your insurer, and those often protect you.

Is there a deadline for a hospital to bill you?

Not one single deadline. No federal rule sets a general time limit for a provider to bill a patient directly. Some states set their own limits, so state rules may add more protection.

Instead, separate time limits apply at different stages. Here are the main ones.

Why bills sometimes arrive late

A late bill doesn't always mean something went wrong. Here are the usual reasons:

• The claim went to the wrong plan. The hospital may have had old insurance details on file.
• 2 plans had to sort out who pays first. If you have more than 1 plan, that can take time.
• Your insurer denied the claim. The hospital may have appealed or resent it before billing you.
• Your insurer took back a payment. A plan can sometimes review a paid claim and ask for money back.
• The bill went to an old address. You may be seeing it for the first time, even though it was sent earlier.
• A separate doctor billed later. Doctors who treated you in the hospital often send their own bills on their own schedule.

What are insurers' filing deadlines?

Every insurer sets a deadline for providers to send claims. It's often called a timely filing limit.

For Original Medicare, federal rules set the deadline. Claims must be filed within 12 months, or 1 calendar year, after the date of service. If you see a doctor on March 22, the claim is due by March 22 of the next year. There are a few exceptions, like a Medicare error or Medicare coverage that started retroactively.

The law requires your provider to file Original Medicare claims for covered care. They can't charge you for filing. If a claim isn't filed in time, Medicare won't pay its share.

Private plans set their own filing limits, often in their contracts with network providers. So the deadline depends on your plan. Your plan's member services team can tell you what it is.

What if the provider missed your insurer's deadline?

When a claim reaches your plan too late, your plan usually denies it. Your explanation of benefits (EOB) may show reason code 29: "The time limit for filing has expired."

If the hospital is in your network, it often can't pass that cost to you. Network providers agree not to bill you more than your share for covered services. A late-filing denial is often labeled CO, for "contractual obligation." That usually means the provider writes it off. The exact rules depend on the hospital's contract and your state's laws.

Original Medicare has a clear rule. If the provider is responsible for missing the deadline, it can't charge you for the services. It can charge only the deductible and coinsurance you would have owed if Medicare had paid.

It can be different if you didn't give the hospital your insurance details, or if it's out of network. In those cases, ask the hospital to explain what you owe and why. Our guide to why a medical bill is higher than the EOB covers other reasons the numbers may not match.

Other time limits worth knowing

Good faith estimates. If you didn't use insurance, you may have gotten a good faith estimate before scheduled care. If the bill is at least $400 more than that provider's estimate, you can dispute it. You must start within 120 days of getting the first bill. See our guide to good faith estimate disputes.

Nonprofit hospitals. Federal tax rules give you at least 240 days after the first bill sent after your care to apply for financial assistance. The hospital must wait at least 120 days after that bill before serious collection steps, like reporting you to a credit bureau or suing you. Our guide to hospital charity care explains how to apply.

Credit reports. As of September 2026, the 3 nationwide credit bureaus wait 1 year before an unpaid medical collection can appear. They also leave off medical collections that started under $500. See our guide to medical debt on your credit report.

Lawsuits. Each state sets a statute of limitations for suing over a debt. The Consumer Financial Protection Bureau says most are 3 to 6 years. In some states, a payment can restart the clock. Our guide to a medical bill in collections explains more.

Say Maya visits an in-network nonprofit hospital's emergency room on January 15, 2026. She shows her new insurance card at check-in. The hospital sends the claim to her old plan by mistake.

On September 1, 2026, Maya gets her first bill: $2,400 for the full charge. She checks her new plan's app. The hospital sent the claim there only in August, past her plan's filing limit, and her plan denied it. Here's her EOB.

Line	Amount
Amount billed	$2,400
Plan paid	$0
Adjustment, code CO-29 (filing limit expired)	−$2,400
You may owe	$0

The EOB shows the late filing as the hospital's write-off, not Maya's share. She calls the billing office, explains that she gave her new card at check-in, and asks them to remove the $2,400.

If the hospital disagrees, Maya still has time. Her window to apply for financial assistance runs at least until April 29, 2027, which is 240 days after September 1. The hospital can't take serious collection steps before December 30, 2026, which is 120 days after that first bill.

What to do when you get a late bill

1. Don't pay right away. Check that the bill is yours, the dates are right, and you got the care listed.
2. Find the EOB or Medicare Summary Notice. Look in your insurer's app or website, or your Medicare.gov account. Our guide to reading a Medicare Summary Notice shows where to look.
3. Ask for the claim history. Call the billing office. Ask when the claim was sent, which insurer got it, and whether it was denied.
4. If your insurer never got the claim, ask them to send it. Ask them to hold your account while they do. Our bill insurance first letter puts that request in writing.
5. If it was denied for late filing, ask them to remove the charge. This is strongest if the hospital is in your network and had your insurance details. Get the answer in writing.
6. Compare the new bill with your EOB. Our guide to EOB vs. medical bill walks through it.
7. If you still owe and can't pay, ask about financial assistance and a payment plan. Do this before the bill goes to collections.

If the hospital won't correct the bill, put your request in writing. Our guide on how to dispute a medical bill shows how.

When to get help

You can often sort out a late bill with 1 or 2 calls. It's worth getting help when:

• The hospital won't remove a charge your EOB shows as its write-off.
• The bill is already in collections, or a collector is calling.
• The debt is several years old and you're not sure your state still allows a lawsuit.
• You're handling an old bill for a parent or someone else.

Call your insurer's member services number, on your insurance card, to confirm when the claim arrived. If your plan isn't helping, contact your state insurance department or consumer assistance program. If you have Medicare, call 1-800-MEDICARE (1-800-633-4227). For a good faith estimate dispute, the No Surprises Help Desk is at 1-800-985-3059.

A medical bill advocate can take on the calls for you. If you're sued over an old bill, talk with a legal aid office or an attorney right away.