ClaimRail / Dental Denial Codes
THE DENTAL DENIAL FIELD GUIDE

Every dental denial code that costs you money — decoded.

Most denied dental claims are never resubmitted — not because they can't be won, but because reading the code, finding the fix, and re-filing before the deadline takes time a busy front office doesn't have. This is the reference for the codes that cost practices the most: what each one actually means, what turns it over, and whether it's a corrected claim or an appeal. Start with the code on your EOB.

CARC / CO — CLAIM ADJUSTMENT REASON CODES
CARC 16 · CO-16
Claim lacks information
The most common dental denial — and the most misread. It's not a rejection; it's "we need more information." Read the paired RARC, fix the one field, resubmit as a corrected claim.
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CARC 197 · CO-197
Precertification / authorization absent
The service required prior authorization that wasn't obtained or wasn't on file. Often recoverable with a retro-auth or by proving the auth existed — before timely filing runs out.
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CARC 29 · CO-29
Timely filing limit expired
The "rotting money" denial — the claim was filed past the payer's window. Recoverable more often than offices think, with proof of timely submission or a valid exception.
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CARC 45
Charge exceeds the fee schedule
The billed amount is above the allowed maximum. Knowing which part is a genuine contractual write-off and which is recoverable is where practices leave money on the table.
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CARC 96 · CO-96
Non-covered charge
Read as "final" by most offices — but "non-covered" often means a documentation or coding gap, or the wrong benefit, not a true exclusion. Frequently overturnable.
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CARC 109
Not covered by this payer
Usually a routing problem, not a coverage problem — the claim went to the wrong payer or the coordination-of-benefits order is off. Send it to the right plan and it pays.
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CARC 50
Not deemed a medical necessity
The documentation didn't establish necessity — often a narrative or radiograph gap, not a real "no." Frequently the trigger to bill medically, where the real money is.
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CARC 18
Duplicate claim / service
A real duplicate is a non-issue — but bilateral, multi-visit, and same-day procedures get falsely flagged as duplicates constantly. The right modifier or documentation unlocks the payment.
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CDT — PROCEDURE-SPECIFIC DENIALS
COVERAGE & FREQUENCY LIMITS
DON'T DECODE THEM ONE AT A TIME

Text us the denial and we'll tell you — free — exactly what turns it over.

Send a photo of the EOB. You'll get back what the code means, whether it's winnable, and what recovers it. If it's worth pursuing, the rail files it.

TEXT A PHOTO OF THE EOB TO 510·401·3633 — FREE AUDIT BACK