Who has to pay after a code 116 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.

All denial codes · code 116

Denial code 116: what it means — and how to fight it

Denial code 116 (shown on your EOB as CO-116 or PR-116) means: “The advance indemnification notice signed by the patient did not comply with requirements.” In plain English: You signed a form agreeing to pay if insurance said no, but the form itself did not meet the rules. That is usually good news for you.

high appealability Usually the provider's problem — not yours

What they're really saying

“The advance indemnification notice signed by the patient did not comply with requirements.”

You signed a form agreeing to pay if insurance said no, but the form itself did not meet the rules. That is usually good news for you.

Your odds

Strong — this type of denial has real weaknesses.

Often means you cannot be billed at all, because a defective notice does not shift cost to you.

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 116 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.
Ask the provider for a copy of the waiver form you signed and read what service it names. Ask for a copy of the notice you signed. A valid advance notice must name the specific service, give a cost estimate, and explain why coverage is expected to be denied. A blanket form signed at check-in usually does not qualify. If it is defective, tell the provider in writing that you dispute the balance.
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 116 mean?: You signed a form agreeing to pay if insurance said no, but the form itself did not meet the rules. That is usually good news for you.
Can I appeal a CO-116 or PR-116 denial?: Yes. Appealing is free and it is your legal right. For this code the odds are high: Often means you cannot be billed at all, because a defective notice does not shift cost to you. Fewer than 1 in 100 denials are ever appealed — insurers count on silence.
Who has to pay after a code 116 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.