Who has to pay after a code 165 denial?

Who owes depends on the details. 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 165

Denial code 165: what it means — and how to fight it

Denial code 165 (shown on your EOB as CO-165 or PR-165) means: “Referral absent or exceeded.” In plain English: Your plan needed a referral from your primary care doctor before this visit, and there was not one — or it had run out of visits.

medium appealability Who owes depends on the details

What they're really saying

“Referral absent or exceeded.”

Your plan needed a referral from your primary care doctor before this visit, and there was not one — or it had run out of visits.

Your odds

Worth fighting — many of these get fixed.

Retroactive referrals are granted fairly often, especially when the PCP agrees the visit was needed.

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 165 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.
Call your primary care office and ask them to file a retroactive referral. Ask your primary care office to submit a retroactive referral with a note on why the specialist visit was necessary. If a referral existed but the visit count was used up, ask for an extension. Check whether your plan type actually requires referrals — many PPO members are denied under this code in error.
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 165 mean?: Your plan needed a referral from your primary care doctor before this visit, and there was not one — or it had run out of visits.
Can I appeal a CO-165 or PR-165 denial?: Yes. Appealing is free and it is your legal right. For this code the odds are medium: Retroactive referrals are granted fairly often, especially when the PCP agrees the visit was needed. Fewer than 1 in 100 denials are ever appealed — insurers count on silence.
Who has to pay after a code 165 denial?: Who owes depends on the details. 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.