Dental claim adjustment codes, explained

What CO-45, PR-2, and the other adjustment codes on a dental EOB or 835 mean, who owes each amount, and what to do next, based on about 2,800 real dental adjustments. Includes every CARC code in one searchable table.

14 min read Updated

What adjustment codes are

When a payer pays less than you charged, it has to say why. It does that with adjustment codes: each dollar between your fee and the payment gets a code that says who is responsible for it and the reason it wasn't paid.

A complete adjustment has three parts:

  • A group code (CO, PR, OA, or PI) that says who is financially responsible for the amount.
  • A Claim Adjustment Reason Code (CARC), such as 45 or 2, that says why the amount was adjusted.
  • Remittance Advice Remark Codes (RARCs), such as N130, when the payer needs to add detail the reason code can't carry.

You'll see them written together as CO-45 or PR-2. Read the group code and the reason code as a pair. The same reason code can mean "write it off" under one group code and "bill the patient" under another.

Paper EOBs often use their own codes. Many dental payers print proprietary explanation codes on the EOB, with a legend on the back or last page. In the claims we looked at (see below), every adjustment on an 835 used a standard CARC, while about one code in six on a PDF EOB was the payer's own. That's one reason 835s are easier to work across payers.

The four group codes

The group code is the first thing to read, because it decides where the money goes.

Group Meaning Who absorbs it What you usually do
CO Contractual Obligation The provider Write it off. Under your contract you can't bill the patient for it.
PR Patient Responsibility The patient Check for secondary coverage, then bill the patient.
OA Other Adjustment Depends on the reason Read the reason and remarks. Often used for prior-payer amounts on secondary claims.
PI Payer Initiated Reduction The provider, per the payer Read the reason. The payer is reducing the amount on its own policy rather than a contract term, so check whether to dispute it.

The codes dental offices actually see

The CARC list has a few hundred codes, but most of them never show up on a dental remittance. To see which ones do, we analyzed a small sample of about 2,800 adjustments on roughly 750 dental claims that RevCanvas processed between July to October 2026. They came from 835 files and PDF EOBs from more than a dozen payers, including Guardian, MetLife, Delta Dental, Cigna, Principal, Aetna, and Blue Cross Blue Shield.

78%

of all adjustments were one of three codes: CO-45, PR-2, or PR-1.

3 in 4

service lines carried only routine codes: the write-off, deductible, coinsurance, or copay.

1 in 5

claims had at least one adjustment that needed follow-up, such as a duplicate, a denial, or a plan limit.

These were the fifteen most common group and reason code pairs, as a share of all adjustments. Payer-specific codes from paper EOBs are left out.

Code What it means Share of adjustments
CO-45 PPO write-off: charge above the contracted fee
55.7%
PR-2 Coinsurance
17.1%
PR-1 Deductible
4.9%
OA-18 Duplicate claim
2.0%
CO-131 Negotiated discount (Delta Dental)
2.0%
OA-A1 Denied; see the remark code
1.8%
PR-96 Not covered by the plan
1.3%
PR-119 Benefit maximum reached
1.2%
PR-A1 Denied; see the remark code
1.0%
PR-3 Copay
1.0%
CO-252 Attachment or documentation required
0.8%
PR-169 Alternate benefit paid
0.6%
PR-27 Coverage had ended
0.6%
PI-B13 Previously paid
0.4%
OA-23 Prior payer's adjudication (secondary claims)
0.4%

The most common service line had a single adjustment, CO-45: the plan paid its full share of the contracted fee and the rest was written off. Half of all lines looked like that. The next most common was CO-45 with PR-2, then CO-45 with PR-1 and PR-2, which is the pattern in the worked example below.

The practical takeaway: most lines can be posted quickly, as long as you confirm the allowance matches your fee schedule. Spend your time on the lines that carry anything else.

Reading an adjustment line: a worked example

Every service line on a remittance balances: the amount charged equals the amount paid plus every adjustment. If the numbers don't add up, something was missed in posting or in the remittance itself.

Take an in-network crown (D2740) billed at $1,200. The plan's contracted fee is $850, the patient has $50 of deductible left, and the plan pays crowns at 50%.

Line Code Amount What it means
Charged$1,200.00Your fee
AdjustmentCO-45−$350.00Above the contracted fee. Write off.
AdjustmentPR-1−$50.00Deductible. Patient owes.
AdjustmentPR-2−$400.0050% coinsurance on the remaining $800. Patient owes.
Paid$400.00The plan's 50%

The patient owes $450 ($50 + $400), the office writes off $350, and $1,200 = $400 + $350 + $50 + $400. In an 835, the same line looks like this:

SVC*AD:D2740*1200*400~
CAS*CO*45*350~
CAS*PR*1*50**2*400~

The SVC segment holds the procedure, the charge, and the payment. Each CAS segment starts with a group code and then lists reason code and amount pairs, so one CAS*PR segment can carry both the deductible and the coinsurance.

CO-45 vs. PR-1, PR-2, and PR-3: who owes what

These codes cover most of the adjustments on a typical PPO remittance:

  • CO-45 is the PPO write-off: the difference between your fee and the contracted fee. If you're in network, it comes off the balance and never goes to the patient.
  • CO-131, "claim specific negotiated discount," does the same job on some Delta Dental plans. In our data it appeared only on Delta Dental remittances, usually next to a PR-3 copay. Treat it as a write-off, like CO-45.
  • PR-1 is the deductible. The patient owes it.
  • PR-2 is coinsurance, the patient's percentage of the allowed amount. The patient owes it.
  • PR-3 is a fixed copay. The patient owes it. Most dental plans use coinsurance, but copay-based plans, including some DHMO plans, use PR-3.

Two situations change the answer:

  • Out-of-network claims. Without a contract, the payer may report the amount above its allowance under PR or OA instead of CO. We saw PR-45 on out-of-network claims for exactly this reason. Whether you can bill the patient for it depends on your agreement with the patient and your state's rules.
  • Secondary coverage. A PR amount from the primary is what the secondary plan looks at. Send the secondary claim before billing the patient, and post the secondary's payment against the same balance. On the secondary's remittance, the primary's payment shows up as OA-23.

Common dental adjustment codes and what to do

These are the reason codes we saw most often, in order. The group code under each is the one payers used in our data, which is typical but not guaranteed: always read the group code the payer actually sent. Other codes that come up on dental claims, such as 16, 22, 29, 97, 151, and 197, are covered in the next section and the full list below.

Code Official description What to do
45 Seen as CO Charge exceeds fee schedule/maximum allowable or contracted/legislated fee arrangement. Write off if in network. Compare the allowance with your fee schedule for that plan to catch underpayments.
2 Seen as PR Coinsurance Amount Check the coinsurance percentage against the plan's benefits for that procedure category, then bill the patient after checking secondary coverage.
1 Seen as PR Deductible Amount Bill the patient after checking secondary coverage. Confirm the deductible against the benefits on file.
18 Seen as OA or CO Exact duplicate claim/service. Find the original claim and its payment before doing anything else. Don't post a second payment.
131 Seen as CO Claim specific negotiated discount. Treat it like CO-45: a write-off, not a patient balance.
A1 Seen as OA or PR Claim/Service denied. At least one Remark Code must be provided (may be comprised of either the NCPDP Reject Reason Code, or Remittance Advice Remark Code that is not an ALERT.) A denial. Read the remark code for the reason. Under PR the patient can usually be billed; under OA, follow up with the payer first.
96 Seen as PR Charges not covered under the plan. Please ensure inclusion of at least one Remark Code. Read the remark code. As PR, the patient can be billed. If it comes as CO, check your contract and state rules first.
119 Seen as PR Benefit maximum for this time period or occurrence has been reached. The annual or lifetime maximum was reached. Bill the patient and note it for the treatment planning team.
3 Seen as PR Co-payment Amount Collect the copay. Check that it matches the plan's copay schedule.
252 Seen as CO An attachment/other documentation is required to adjudicate this claim/service. Send the requested attachment: x-rays, perio charting, or a narrative. Common on crowns, buildups, and scaling and root planing.
169 Seen as PR Alternate benefit has been provided. The plan paid for a less expensive alternative, such as paying a posterior composite at the amalgam rate. The difference is usually the patient's. Tell them before similar treatment.
27 Seen as PR Expenses incurred after coverage terminated. Verify eligibility on the date of service. If the patient had other coverage then, bill that plan.
B13 Seen as PI Previously paid. Payment for this claim/service may have been provided in a previous payment. The payer says it already paid this. Find the earlier payment before posting anything, the same as a duplicate.
23 Seen as OA The impact of prior payer(s) adjudication including payments and/or adjustments. Seen on secondary claims. Check that the primary's payment and adjustments were reported correctly.
273 Seen as PR Coverage/program guidelines were exceeded. A plan guideline was exceeded, often a frequency or age limit. Read the remark code and the plan's guidelines.
204 Seen as PR This service/equipment/drug is not covered under the patient’s current benefit plan Confirm the exclusion in the plan's benefits. Note it for treatment planning so the patient knows before the next visit.
225 Seen as PI Penalty or Interest Payment by Payer. Interest the payer added for paying late. It increases the payment rather than reducing it, so account for it when you reconcile the deposit.

Codes that need follow-up

About one claim in five had at least one adjustment outside the routine write-off, deductible, coinsurance, and copay. A denial is one of these: an adjustment that takes the payment to zero. It uses the same group and reason codes as any other adjustment, so the first step is the same. Read the codes and decide which kind of problem it is.

  • Duplicates and earlier payments (18, B13): the most common non-routine adjustment we saw, and an expensive one. Duplicate lines averaged about $160, nearly three times the average CO-45 write-off. They usually mean a claim was resubmitted while the first was still processing. Find the original payment and don't post anything new.
  • Denials that rely on a remark (A1, 16): the reason is in the remark code. Correct the claim or send what's missing, then resubmit.
  • Plan limits and exclusions (119, 96, 169, 204, 273): confirm the limit applies. If it does, it's usually the patient's responsibility, and the treatment planning team should know about it.
  • Missing documentation (252, often with remark N706): send the x-rays, charting, or narrative the payer asked for.
  • Coverage and eligibility (27, 22, 109): check the patient's coverage on the date of service and bill the right plan, or move the balance to the patient if it's truly not covered.
  • Process problems (29, 197): these are often write-offs unless you can show the claim was filed on time or the authorization existed.
  • Payer judgment (50, 97): these are the ones worth appealing when your documentation supports the service as billed.

Before resubmitting, check whether the payer wants a corrected claim or an appeal. Sending a new claim for a service the payer already processed is how many of those 18 duplicates start.

Remark codes (RARCs)

Remittance Advice Remark Codes add detail the reason code can't carry. They start with M, MA, or N. Codes that start with "Alert:" are informational. The rest explain the adjustment.

Some CARCs require a remark. 16, 96, 129, 234, and A1 all tell the payer to include at least one, so if you see one of those without a remark, ask the payer what it means. In an 835, remarks appear in the LQ segment for a single service line and in the MOA segment for the whole claim.

The first ten below are the remarks we saw most often on dental 835s, in order. The rest are others worth knowing.

Code Description
N130 Consult plan benefit documents/guidelines for information about restrictions for this service.
N640 Exceeds number/frequency approved/allowed within time period.
N706 Missing documentation.
N479 Missing Explanation of Benefits (Coordination of Benefits or Medicare Secondary Payer).
N129 Not eligible due to the patient's age.
M86 Service denied because payment already made for same/similar procedure within set time frame.
M15 Separately billed services/tests have been bundled as they are considered components of the same procedure. Separate payment is not allowed.
MA92 Missing plan information for other insurance.
N22 This procedure code was added/changed because it more accurately describes the services rendered.
MA04 Secondary payment cannot be considered without the identity of or payment information from the primary payer. The information was either not reported or was illegible.
N37 Missing/incomplete/invalid tooth number/letter.
N39 Procedure code is not compatible with tooth number/letter.
N20 Service not payable with other service rendered on the same date.
N381 Alert: Consult our contractual agreement for restrictions/billing/payment information related to these charges.
N211 Alert: You may not appeal this decision.

Every CARC code, searchable

The full list of Claim Adjustment Reason Codes from the X12 code list (2025). Search by code (45, CO-45) or by any words in the description. Property and casualty and workers' compensation codes (the P codes) are left out because they don't apply to dental claims.

265 codes

Code Description
1 Deductible Amount
2 Coinsurance Amount
3 Co-payment Amount
4 The procedure code does not match the used modifier.
5 The procedure code/type of bill is inconsistent with the place of service.
6 The procedure/revenue code is inconsistent with the patient’s age.
7 The procedure/revenue code is inconsistent with the patient’s gender.
8 The procedure code is inconsistent with the provider type/specialty (taxonomy).
9 The diagnosis is inconsistent with the patient’s age.
10 The diagnosis is inconsistent with the patient’s gender.
11 The diagnosis is inconsistent with the procedure.
12 The diagnosis is inconsistent with the provider type.
13 The date of death precedes the date of service.
14 The date of birth follows the date of service.
15 The authorization number is missing, invalid, or does not apply to the billed services or provider.
16 Claim/service lacks information or has submission/billing error(s).
17 Requested information was not provided or was insufficient/incomplete.
18 Exact duplicate claim/service.
19 This is a work-related injury/illness and thus the liability of the Worker’s Compensation Carrier.
20 This injury/illness is covered by the liability carrier.
21 This injury/illness is the liability of the no-fault carrier.
22 This care may be covered by another payer per coordination of benefits.
23 The impact of prior payer(s) adjudication including payments and/or adjustments.
24 Charges are covered under a capitation agreement/managed care plan.
26 Expenses incurred prior to coverage.
27 Expenses incurred after coverage terminated.
29 The time limit for filing has expired.
31 Patient cannot be identified as our insured.
32 Our records indicate the patient is not an eligible dependent.
33 Insured has no dependent coverage.
34 Insured has no coverage for newborns.
35 Lifetime benefit maximum has been reached.
39 Services denied at the time authorization/pre-certification was requested.
40 Charges do not meet qualifications for emergent/urgent care.
44 Prompt-pay discount.
45 Charge exceeds fee schedule/maximum allowable or contracted/legislated fee arrangement.
49 This service is not covered as it falls under a routine/preventive examination or a diagnostic/screening procedure conducted alongside a routine/preventive exam.
50 These are non-covered services because this is not deemed a ‘medical necessity’ by the payer.
51 These are non-covered services because this is a pre-existing condition.
53 Services by an immediate relative or a member of the same household are not covered.
54 Multiple physicians/assistants are not covered in this case.
55 Procedure/treatment/drug is deemed experimental/investigational by the payer.
56 Procedure/treatment has not been deemed ‘proven to be effective’ by the payer.
58 Treatment was deemed by the payer to have been rendered in an inappropriate or invalid place of service.
59 Handled according to guidelines for multiple or concurrent procedures, such as multiple surgeries, diagnostic imaging, or concurrent anesthesia.
60 Charges for outpatient services are not covered when performed within a period of time prior to or after inpatient services.
61 Adjusted for failure to obtain second surgical opinion
66 Blood Deductible.
69 Day outlier amount.
70 Cost outlier – Adjustment to compensate for additional costs.
74 Indirect Medical Education Adjustment.
75 Direct Medical Education Adjustment.
76 Disproportionate Share Adjustment.
78 Non-Covered days/Room charge adjustment.
85 Patient Interest Adjustment.
89 Professional fees removed from charges.
90 Ingredient cost adjustment. Usage: To be used for pharmaceuticals only.
91 Dispensing fee adjustment.
94 Processed in Excess of charges.
95 Plan procedures not followed.
96 Charges not covered under the plan. Please ensure inclusion of at least one Remark Code.
97 The benefit for this service is included in the payment/allowance for another service/procedure that has already been adjudicated.
100 Payment made to patient/insured/responsible party.
101 Predetermination: anticipated payment upon completion of services or claim adjudication.
102 Major Medical Adjustment.
103 Provider promotional discount (Eg. Senior citizen discount).
104 Managed care withholding.
105 Tax withholding.
106 Patient payment option/election not in effect.
107 The related or qualifying claim/service was not identified on this claim.
108 Rent/purchase guidelines were not met.
109 Claim/service not covered by this payer/contractor. You must send the claim/service to the correct payer/contractor.
110 Billing date predates service date.
111 Not covered unless the provider accepts assignment.
112 Service not furnished directly to the patient and/or not documented.
114 Procedure/product not approved by the Food and Drug Administration.
115 Procedure postponed, canceled, or delayed.
116 The advance indemnification notice signed by the patient did not comply with requirements.
117 Transportation is only covered to the closest facility that can provide the necessary care.
118 ESRD network support adjustment.
119 Benefit maximum for this time period or occurrence has been reached.
121 Indemnification adjustment – compensation for outstanding member responsibility.
122 Psychiatric reduction.
128 Newborn’s services are covered in the mother’s Allowance.
129 Prior processing information appears incorrect. At least one Remark Code must be provided.
130 Claim submission fee.
131 Claim specific negotiated discount.
132 Prearranged demonstration project adjustment.
133 The disposition of this service line is pending further review.
134 Technical fees removed from charges.
135 Interim bills cannot be processed.
136 Failure to follow prior payer’s coverage rules.
137 Regulatory Surcharges, Assessments, Allowances or Health Related Taxes.
139 Contracted funding agreement – Subscriber is employed by the provider of services.
140 Patient/Insured health identification number and name do not match.
142 Monthly Medicaid patient liability amount.
143 Portion of payment deferred.
144 Incentive adjustment, e.g. preferred product/service.
146 Diagnosis was invalid for the date(s) of service reported.
147 Provider contracted/negotiated rate expired or not on file.
148 Information from another provider was not provided or was insufficient/incomplete.
149 Lifetime benefit maximum has been reached for this service/benefit category.
150 Payer deems the information submitted does not support this level of service.
151 Payment adjusted because the payer deems the information submitted does not support this many/frequency of services.
152 Payer deems the information submitted does not support this length of service.
153 Payer deems the information submitted does not support this dosage.
154 Payer deems the information submitted does not support this day’s supply.
155 Patient refused the service/procedure.
157 Service/procedure was provided as a result of an act of war.
158 Service/procedure was provided outside of the United States.
159 Service/procedure was provided as a result of terrorism.
160 Injury/illness was the result of an activity that is a benefit exclusion.
161 Provider performance bonus
163 Attachment/other documentation referenced on the claim was not received.
164 Attachment/other documentation referenced on the claim was not received in a timely fashion.
166 These services were submitted after this payers responsibility for processing claims under this plan ended.
167 This diagnosis is not covered.
169 Alternate benefit has been provided.
170 Payment is denied when performed/billed by this type of provider.
171 Payment is denied when performed/billed by this type of provider in this type of facility.
172 Payment is adjusted when performed/billed by a provider of this specialty.
173 Service/equipment was not prescribed by a physician.
174 Service was not prescribed prior to delivery.
175 Prescription is incomplete.
176 Prescription is not current.
177 Patient has not met the required eligibility requirements.
178 Patient has not met the required spend down requirements.
179 Patient has not met the required waiting requirements.
180 Patient has not met the required residency requirements.
181 Procedure code was invalid on the date of service.
182 Procedure modifier was invalid on the date of service.
183 The referring provider is not eligible to refer the service billed.
184 The prescribing/ordering provider is not eligible to prescribe/order the service billed.
185 The rendering provider is not eligible to perform the service billed.
186 Level of care change adjustment.
187 Consumer Spending Account payments (includes but is not limited to Flexible Spending Account, Health Savings Account, Health Reimbursement Account, etc.)
188 This product/procedure is only covered when used according to FDA recommendations.
189 Not otherwise classified’ or ‘unlisted’ procedure code (CPT/HCPCS) was billed when there is a specific procedure code for this procedure/service
190 Payment is included in the allowance for a Skilled Nursing Facility (SNF) qualified stay.
192 Non standard adjustment code from paper remittance. Usage: This code is to be used by providers/payers providing Coordination of Benefits information to another payer in the 837 transaction only. This code is only used when the non- standard code cannot be reasonably mapped to an existing Claims Adjustment Reason Code, specifically Deductible, Coinsurance and Co-payment.
193 Original payment decision is being maintained. Upon review, it was determined that this claim was processed properly.
194 Anesthesia performed by the operating physician, the assistant surgeon or the attending physician.
195 Refund issued to an erroneous priority payer for this claim/service.
197 Precertification/authorization/notification/pre-treatment absent.
198 Precertification/notification/authorization/pre-treatment exceeded.
199 Revenue code and Procedure code do not match.
200 Expenses incurred during lapse in coverage
201 Patient is responsible for amount of this claim/service through ‘set aside arrangement’ or other agreement.
202 Non-covered personal comfort or convenience services.
203 Discontinued or reduced service.
204 This service/equipment/drug is not covered under the patient’s current benefit plan
205 Pharmacy discount card processing fee
206 National Provider Identifier – missing.
207 National Provider identifier – Invalid format
208 National Provider Identifier – Not matched.
209 Per regulatory or other agreement. The provider cannot collect this amount from the patient. However, this amount may be billed to subsequent payer. Refund to patient if collected.
210 Payment adjusted because pre-certification/authorization not received in a timely fashion
211 National Drug Codes (NDC) not eligible for rebate, are not covered.
212 Administrative surcharges are not covered
213 Non-compliance with the physician self referral prohibition legislation or payer policy.
215 Based on subrogation of a third party settlement
216 Based on the findings of a review organization
219 Determined by the severity of the injury. If the adjustment is made at the Claim Level, the payer is required to send and the provider should consult the 835 Insurance Policy Number Segment for jurisdictional regulations.
222 Exceeds the contracted maximum number of hours/days/units by this provider for this period. This is not patient specific.
223 Adjustment code for mandated federal, state or local law/regulation that is not already covered by another code and is mandated before a new code can be created.
224 Patient identification compromised by identity theft. Identity verification required for processing this and future claims.
225 Penalty or Interest Payment by Payer.
226 The information requested from the Billing/Rendering Provider was either not provided, not provided in a timely manner, or was insufficient/incomplete. It is necessary to include at least one Remark Code.
227 Information requested from the patient/insured/responsible party was not provided or was insufficient/incomplete. At least one Remark Code must be provided (may be comprised of either the NCPDP Reject Reason Code, or Remittance Advice Remark Code that is not an ALERT.)
228 Denied for failure of this provider, another provider or the subscriber to supply requested information to a previous payer for their adjudication
229 Partial charge amount not considered by Medicare due to the initial claim Type of Bill being 12X. Usage: This code can only be used in the 837 transaction to convey Coordination of Benefits information when the secondary payer’s cost avoidance policy allows providers to bypass claim submission to a prior payer. (Use only with Group Code PR)
231 Mutually exclusive procedures cannot be done in the same day/setting.
232 Institutional Transfer Amount. Usage: Applies to institutional claims only and explains the DRG amount difference when the patient care crosses multiple institutions.
233 Services/charges related to the treatment of a hospital-acquired condition or preventable medical error.
234 This procedure is not paid separately. At least one Remark Code must be provided (may be comprised of either the NCPDP Reject Reason Code, or Remittance Advice Remark Code that is not an ALERT.)
235 Sales Tax
236 This procedure or procedure/modifier combination is not compatible with another procedure or procedure/modifier combination provided on the same day according to the National Correct Coding Initiative or workers compensation state regulations/ fee schedule requirements.
237 Legislated/Regulatory Penalty. At least one Remark Code must be provided (may be comprised of either the NCPDP Reject Reason Code, or Remittance Advice Remark Code that is not an ALERT.)
238 Claim spans eligible and ineligible periods of coverage, this is the reduction for the ineligible period. (Use only with Group Code PR)
239 Claim spans eligible and ineligible periods of coverage. Rebill separate claims.
240 The diagnosis is inconsistent with the patient’s birth weight.
241 Low Income Subsidy (LIS) Co-payment Amount
242 Services not provided by network/primary care providers.
243 Services not authorized by network/primary care providers.
245 Provider performance program withhold.
246 This non-payable code is for required reporting only.
247 Deductible for Professional service rendered in an Institutional setting and billed on an Institutional claim.
248 Coinsurance for Professional service rendered in an Institutional setting and billed on an Institutional claim.
249 This claim has been identified as a readmission. (Use only with Group Code CO)
250 The attachment or other documentation that was received is not the correct attachment or document. The anticipated attachment or document is still absent.
251 The attachment or other documentation that was received is incomplete or deficient. Essential information is still required to process the claim.
252 An attachment/other documentation is required to adjudicate this claim/service.
253 Sequestration – reduction in federal payment
254 Claim received by the dental plan, but benefits not available under this plan. Submit these services to the patient’s medical plan for further consideration.
256 Service not payable per managed care contract.
257 The status of the claim or service is uncertain during the grace period for premium payment, as mandated by Health Insurance Exchange regulations. This claim or service will be reversed and rectified after the grace period concludes, whether due to premium payment or lack thereof. (Use this code solely with Group Code OA).
258 Claim/service not covered when patient is in custody/incarcerated. Applicable federal, state or local authority may cover the claim/service.
259 Additional payment for Dental/Vision service utilization.
260 Processed under Medicaid ACA Enhanced Fee Schedule
261 The procedure or service is inconsistent with the patient’s history.
262 Adjustment for delivery cost. Usage: To be used for pharmaceuticals only.
263 Adjustment for shipping cost. Usage: To be used for pharmaceuticals only.
264 Adjustment for postage cost. Usage: To be used for pharmaceuticals only.
265 Adjustment for administrative cost. Usage: To be used for pharmaceuticals only.
266 Adjustment for compound preparation cost. Usage: To be used for pharmaceuticals only.
267 Claim/service spans multiple months. At least one Remark Code must be provided (may be comprised of either the NCPDP Reject Reason Code, or Remittance Advice Remark Code that is not an ALERT.)
268 The Claim spans two calendar years. Please resubmit one claim per calendar year.
269 Anesthesia not covered for this service/procedure.
270 Claim received by the medical plan, but benefits not available under this plan. Submit these services to the patient’s dental plan for further consideration.
271 Prior contractual reductions related to a current periodic payment as part of a contractual payment schedule when deferred amounts have been previously reported. (Use only with Group Code OA)
272 Coverage/program guidelines were not met.
273 Coverage/program guidelines were exceeded.
274 Fee/Service not payable per patient Care Coordination arrangement.
275 Prior payer’s (or payers’) patient responsibility (deductible, coinsurance, co-payment) not covered. (Use only with Group Code PR)
276 Services denied by the prior payers are not covered by this payer.
277 The disposition of the claim/service is undetermined during the premium payment grace period, per Health Insurance SHOP Exchange requirements. This claim/service will be reversed and corrected when the grace period ends (due to premium payment or lack of premium payment). (Use only with Group Code OA)
278 Performance program proficiency requirements not met.
279 Services not provided by Preferred network providers. Usage: Use this code when there are member network limitations. For example, using contracted providers not in the member’s ‘narrow’ network.
280 Claim received by the medical plan, but benefits not available under this plan. Submit these services to the patient’s Pharmacy plan for further consideration.
281 Deductible waived per contractual agreement. Use only with Group Code CO.
282 The procedure/revenue code is inconsistent with the type of bill.
283 Attending provider is not eligible to provide direction of care.
284 Precertification/authorization/notification/pre-treatment number may be valid but does not apply to the billed services.
285 Appeal procedures not followed
286 Appeal time limits not met
287 Referral exceeded
288 Referral absent
289 Services considered under the dental and medical plans, benefits not available.
290 Claim received by the dental plan, but benefits not available under this plan. Claim has been forwarded to the patient’s medical plan for further consideration.
291 Claim received by the medical plan, but benefits not available under this plan. Claim has been forwarded to the patient’s dental plan for further consideration.
292 Claim received by the medical plan, but benefits not available under this plan. Claim has been forwarded to the patient’s pharmacy plan for further consideration.
293 Payment made to employer.
294 Payment made to attorney.
295 Pharmacy Direct/Indirect Remuneration (DIR)
296 Precertification/authorization/notification/pre-treatment number may be valid but does not apply to the provider.
297 Claim received by the medical plan, but benefits not available under this plan. Submit these services to the patient’s vision plan for further consideration.
298 Claim received by the medical plan, but benefits not available under this plan. Claim has been forwarded to the patient’s vision plan for further consideration.
299 The billing provider is not eligible to receive payment for the service billed.
300 The claim has been received by the Medical Plan; however, the benefits are not covered under this particular plan. The claim has been subsequently referred to the patient’s Behavioral Health Plan for further evaluation and consideration.
301 Claim received by the Medical Plan, but benefits not available under this plan. Submit these services to the patient’s Behavioral Health Plan for further consideration.
302 Precertification/notification/authorization/pre-treatment time limit has expired.
303 Prior payer’s (or payers’) patient responsibility (deductible, coinsurance, co-payment) not covered for Qualified Medicare and Medicaid Beneficiaries. (Use only with Group Code CO)
304 Claim received by the medical plan, but benefits not available under this plan. Submit these services to the patient’s hearing plan for further consideration.
305 Claim received by the medical plan, but benefits not available under this plan. Claim has been forwarded to the patient’s hearing plan for further consideration.
A0 Patient refund amount.
A1 Claim/Service denied. At least one Remark Code must be provided (may be comprised of either the NCPDP Reject Reason Code, or Remittance Advice Remark Code that is not an ALERT.)
A5 Medicare Claim PPS Capital Cost Outlier Amount.
A6 Prior hospitalization or 30 day transfer requirement not met.
A8 Ungroupable DRG.
B1 Non-covered visits.
B10 Allowed amount has been reduced because a component of the basic procedure/test was paid. The beneficiary is not liable for more than the charge limit for the basic procedure/test.
B11 The claim/service has been transferred to the proper payer/processor for processing. Claim/service not covered by this payer/processor. (CARC b11)
B12 Services not documented in patient’s medical records.
B13 Previously paid. Payment for this claim/service may have been provided in a previous payment.
B14 Only one visit or consultation per physician per day is covered.
B15 This service/procedure requires that a qualifying service/procedure be received and covered. The qualifying other service/procedure has not been received/adjudicated.
B16 New Patient’ qualifications were not met.
B20 Procedure/service was partially or fully furnished by another provider.
B22 This payment is adjusted based on the diagnosis.
B23 Procedure billed is not authorized per your Clinical Laboratory Improvement Amendment (CLIA) proficiency test.
B4 Late filing penalty.
B5 Coverage/program guidelines were not met or were exceeded.
B7 This provider was not certified/eligible to be paid for this procedure/service on this date of service.
B8 Alternative services were available, and should have been utilized.
B9 Patient is enrolled in a Hospice.

Common questions

What are the most common dental claim adjustment codes?

Across a small sample of about 2,800 adjustments on roughly 750 dental claims processed by RevCanvas, CO-45 (charge above the contracted fee) made up more than half, followed by PR-2 (coinsurance) and PR-1 (deductible). Those three accounted for 78% of all adjustments. The most common codes needing follow-up were OA-18 (duplicate claim), CO-131 (a negotiated discount Delta Dental uses like CO-45), and A1 (denied; see the remark code).

What does CO-45 mean on a dental EOB?

CO-45 means the fee you charged is higher than the amount your contract with the payer allows. CO (Contractual Obligation) puts the difference on the provider, so an in-network office writes it off and does not bill it to the patient.

What is the difference between a CARC and a RARC?

A Claim Adjustment Reason Code (CARC) says why an amount was adjusted, such as a deductible or a fee schedule reduction. A Remittance Advice Remark Code (RARC) adds detail the CARC can't carry, such as which plan limitation applied or what documentation is missing. Some CARCs, including 16, 96, and A1, require at least one RARC.

Can I bill the patient for a PR adjustment?

Usually, yes. PR (Patient Responsibility) amounts such as deductibles, coinsurance, and copays are the patient's to pay. Check for secondary coverage first, because a secondary plan may pick up some or all of the primary's patient responsibility.

Why don't the codes on my paper EOB match the CARC list?

Many dental payers print their own explanation codes on EOBs, with a legend on the back or last page. The 835 for the same payment must use the standard CARC and RARC codes, so if you receive both, the 835 is the easier one to compare across payers.

Is a denial the same as an adjustment?

A denial is an adjustment that takes the paid amount to zero. It is reported with the same group and reason codes as any other adjustment, so read the codes to decide whether to correct and resubmit, appeal, bill the patient, or write it off.

Keep your dental claims moving, from upload to posting.

Upload your EOBs, 835s, and other documents. RevCanvas extracts the details, assigns claims to the right team member and location, and matches payments to bank transactions so your team knows when to post. Track progress with claim statuses and @-comments, with role-based access that lets managers follow the work.

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