Who has to pay after a code 29 denial?

Usually the provider's problem — not yours. The letters in front of the number matter: CO (contractual obligation) usually means an in-network provider must absorb it, while PR (patient responsibility) means the plan says you owe it.

How long do I have to appeal?

It depends on your coverage: 180 days for most employer and marketplace plans, 120 days for Original Medicare, about 90 days for Medicaid (varies by state), and only 65 days for Medicare Advantage. Set your deadline clock before you do anything else.

Denial code 29 · CO-29 / PR-29 · translated

Denial code 29: what it means — and how to fight it

Denial code 29 (shown on your EOB as CO-29 or PR-29) means: “The time limit for filing has expired.” In plain English: The provider sent the bill too late. In-network providers usually must eat this — not you.

medium appealability Usually the provider's problem — not yours

What they're really saying

“The time limit for filing has expired.”

The provider sent the bill too late. In-network providers usually must eat this — not you.

Your odds

Worth fighting — many of these get fixed.

Patients are typically protected by network contracts.

Fewer than 1 in 100 denied claims are ever appealed. When people do appeal, roughly 4 in 10 win the first round — and independent external review overturns 40–50% of what reaches it.

How to appeal a code 29 denial

Decode. You just did — this page is step one.
Set your clock. 180 days for most employer and marketplace plans, 120 for Original Medicare, ~90 for Medicaid, only 65 for Medicare Advantage.
Urgent? If this is care you still need, call and request an expedited appeal — they must decide within 72 hours.
If in-network, tell the provider in writing that timely-filing denials are not billable to you. In-network contracts almost always bar billing the patient for the provider's late filing. Point this out in writing to the provider.
Send it certified. Letter plus evidence, keep copies of everything.
Escalate. Denied again? Independent external review — a doctor who doesn't work for your insurer decides.

Do it in minutes, free

The AppealClock tool translates your denial, drafts your appeal letter, computes your exact deadline — and watches the clock so you don't have to. No account. Your medical details never leave your device.

Start your appeal & set your clock →

Common questions

What does denial code 29 mean?: The provider sent the bill too late. In-network providers usually must eat this — not you.
Can I appeal a CO-29 or PR-29 denial?: Yes. Appealing is free and it is your legal right. For this code the odds are medium: Patients are typically protected by network contracts. Fewer than 1 in 100 denials are ever appealed — insurers count on silence.
Who has to pay after a code 29 denial?: Usually the provider's problem — not yours. The letters in front of the number matter: CO (contractual obligation) usually means an in-network provider must absorb it, while PR (patient responsibility) means the plan says you owe it.
How long do I have to appeal?: It depends on your coverage: 180 days for most employer and marketplace plans, 120 days for Original Medicare, about 90 days for Medicaid (varies by state), and only 65 days for Medicare Advantage. Set your deadline clock before you do anything else.