PR 31 Denial Code: Patient Not Identified (PR)

Official CARC description: “Patient cannot be identified as our insured.” Here’s what it actually means, why it fires, and how to get the claim paid.

Patient Responsibility (PR)Fix steps belowFree appeal letter draftNo PHI needed

What PR 31 actually means

PR-grouped twin of CO 31 — the payer additionally implies the patient can be billed. Don't statement anyone until identity work is done; it's nearly always fixable data.

Liability group: PR = Patient Responsibility — the amount can be billed to the patient (deductible, coinsurance, non-covered care) — but only after you verify the denial is correct. Mis-grouped PR denials are a common appeal win.

Also written: PR-31, PR31, “denial code 31”, “31 denial code” or “reason code 31” — same CARC, different ERA formatting.

PR 31 vs CO 31 — same number, different liability

Reason code 31 also appears under another group on the ERA. The number is the reason; the prefix decides who absorbs the money. This page covers PR 31 (Patient Responsibility). If your ERA shows a different prefix, use the matching page:

Why PR 31 fires

How to fix PR 31

1

Step 1

Verify against the physical card and a fresh 271

2

Step 2

Newborns: most plans allow 30-day retro-enrollment — resubmit after

3

Step 3

Coverage discovery tools before writing off or statementing

4

Step 4

Correct and resubmit; keep original submission proof

Appeal it — or fix and resubmit?

No merits appeal — identity correction plus resubmission. Newborn retro-enrollment claims deserve a reprocessing request with the enrollment confirmation.

Draft a PR 31 appeal letter now ↓

Draft the appeal letter

Fill in the denial facts — use placeholders, never real patient data (the letter keeps [PATIENT NAME]-style fields so you can merge real details privately). A payer-ready draft with an enclosure checklist comes back in ~20 seconds.

Your appeal letter draft will appear here.

Frequently asked questions

What is the PR 31 denial code description?

The official CARC description for PR 31 is: “Patient cannot be identified as our insured.” In practice: PR-grouped twin of CO 31 — the payer additionally implies the patient can be billed. Don't statement anyone until identity work is done; it's nearly always fixable data.

What does denial code 31 mean on an EOB?

Denial code 31 under the PR group (Patient Responsibility) means: Patient cannot be identified as our insured. The number is the reason; the PR prefix decides who is liable — the amount can be billed to the patient (deductible, coinsurance, non-covered care) — but only after you verify the denial is correct. Mis-grouped PR denials are a common appeal win.

Is PR-31 the same as PR31 or “denial code 31”?

Yes. PR 31, PR-31, PR31 and “denial code 31” are the same CARC — clearinghouses, payer portals and PM systems just print it differently. Only the group prefix (CO, PR, OA or PI) changes the meaning, because it changes who has to absorb the amount.

Is PR 31 the provider’s write-off or the patient’s responsibility?

PR stands for Patient Responsibility — the amount can be billed to the patient (deductible, coinsurance, non-covered care) — but only after you verify the denial is correct. Mis-grouped PR denials are a common appeal win.

Can you appeal a PR 31 denial?

No merits appeal — identity correction plus resubmission. Newborn retro-enrollment claims deserve a reprocessing request with the enrollment confirmation.

What is the difference between PR 31 and CO 31?

The number 31 is the same reason code in both — what changes is the liability group. CO 31 is Contractual Obligation. PR 31 is Patient Responsibility, so the amount can be billed to the patient (deductible, coinsurance, non-covered care). Check the prefix on the ERA before you write anything off or bill the patient — a mis-grouped 31 is one of the more winnable appeals.

Related denial codes