PR-37 Denial Code (Deactivated): Balance Under Deductible
PR-37 meant the whole allowed balance fell within the patient's unmet deductible, so the plan paid nothing on it. X12 deactivated the code without naming a successor; payers now report the deductible portion with CARC 1 under group PR.
X12 deactivated CARC37 on October 16, 2003. Payers should no longer use it on new remittances, but it can still appear on older ERAs, corrected claims, and appeals.
Quick facts
- Code
- PR-37 (CARC 37)
- Status
- Deactivated StoppedOctober 16, 2003 (in use since January 1, 1995).
- Code set
- Claim Adjustment Reason Codes (CARC)
- Group codes
-
- PR (Patient Responsibility): The balance counted toward the member's deductible and was the patient's to pay.
- Official description
Balance does not exceed deductible.
X12 Claim Adjustment Reason Codes, retrieved September 25, 2026- Last verified
- against the official X12 list.
What PR-37 meant
CARC 37 covered the early-in-the-year situation many practices know well. The patient had a deductible that was not yet met, and the allowed amount for this service was small enough that all of it went toward that deductible. The payer therefore paid zero and used code 37 to say why. The amount was the member’s responsibility, which is why it appeared with the PR group.
What replaced it
There is no named successor in the official text. Current remittances show the same outcome with PR-1, the deductible amount code. The contractual reduction that brings the billed charge down to the allowed amount is reported separately as CO-45. If the deductible in question is the blood deductible, payers use PR-66.
If you still see PR-37
It mostly lives on in historical payment reports and old conversions of remittance data. If it shows up on something recent, the payer’s system may be mapping an old code; the handling does not change.
Confirm the allowed amount matches your contract, post the contractual portion as a write-off, and bill the patient for the deductible amount. If the patient has secondary coverage, send the claim on, since many secondary plans consider the primary’s deductible.
Related and easily confused codes
- PR-1 (Deductible Amount): The active deductible code, used with PR for the amount applied to the patient's deductible.
- CO-45 (Charge exceeds fee schedule/maximum allowable or contracted/legislated fee arrangement.): Shows the reduction from billed charge to allowed amount before the deductible is applied.
- PR-66 (Blood Deductible.): Blood deductible, a separate deductible that applies to blood products.
PR-37 FAQ
Does a PR-37 line mean the claim was denied?
No. The service was covered, but the patient had not yet satisfied the deductible, so the full allowed amount was applied to it and the payer's share was zero.
How do I post an old PR-37?
Post it like a deductible line: write off any contractual reduction, then move the allowed amount to patient responsibility.