10 Reasons Dental Insurance Claims May Be Denied

Dental insurance claims are denied or rejected for many reasons. Most of them fall into three groups:

• Coding mistakes
• Documentation mistakes
• Administrative mistakes

The ten reasons below are possible explanations to investigate, not universal denial rules. Read the payer’s explanation of benefits (EOB) and the patient’s plan terms. Out-of-network benefits, authorization requirements and exclusions vary by plan. Work out whether you have a rejected submission or an adjudicated denial before choosing a correction or an appeal.

Ten common reasons for a dental claim denial

1. The patient is no longer covered by the plan

Coverage can end or change between visits. Check eligibility for the date of service before the appointment, not only when the patient first registers.

2. The plan’s out-of-network rules limit or exclude the benefit

Some plans pay a reduced benefit, or none, when the treating dentist is outside the plan’s network. Confirm the dentist’s network status with that plan and how out-of-network services are paid before treatment.

3. The plan decided a lower level of service was appropriate

A plan may base its payment on a less costly procedure than the one reported. Read the EOB remark and the plan’s alternate benefit terms, then decide whether the clinical record supports an appeal.

4. The claim information was incomplete

A missing field, attachment, member ID or provider detail can stop a claim. Review each claim against the payer’s submission checklist before it goes out.

5. Diagnosis and procedure codes were not linked correctly

Where a plan requires diagnosis codes, each one has to point to the procedure it supports. This comes up most often when a dental procedure is billed to a medical plan.

6. The plan decided the service was not necessary

The plan’s reviewer did not find enough support for the treatment in what was submitted. Check which radiographs, charting or narrative the plan asks for with that procedure and whether they were sent.

7. A required authorization or referral was missing

Some plans require approval before certain services. Find out during benefit verification whether the planned procedure needs one, and keep the reference with the claim.

8. Separate codes were reported for a bundled service

A plan may treat one reported procedure as part of another and pay only one of them. Read the EOB remark and the plan’s processing policy before resubmitting or appealing.

9. The plan does not cover the service

Some services are not benefits of a particular plan at all. Verifying benefits before treatment lets the practice tell the patient what the plan is expected to pay.

10. A plan-specific exclusion or limitation applies

Frequency limits, waiting periods, annual maximums and missing tooth clauses are common examples. Check the patient’s history and remaining benefits with the plan before treatment.

Check procedure-specific documentation before submitting

Missing documentation can lead to a claim denial. Delta Dental’s October 2025 guidance gives procedure-specific examples: for certain crown claims, it calls for a pre-operative periapical radiograph showing the entire tooth, including the root tip; for listed periodontal procedures, it calls for radiographs, periodontal charting and chart notes.

These are examples from that payer’s guidance, not a universal checklist for every dental plan. For Delta Dental claims, consult the applicable Provider Handbook in Provider Tools for documentation lists and claims-processing policies.

Source: Delta Dental: Stop claim denials before they even start (October 7, 2025).

If you disagree with a denial

If you do not agree with the reason the insurance company gave, you can file an appeal supported by documentation. Depending on the insurance company, an appeal may mean filling out a form, sending a letter or completing an online appeal process.

Follow the particular plan’s appeal instructions for the required form, destination and filing deadline, and include the supporting documentation. The ADA’s 2020 appeal guide explains why the plan’s specific requirements matter; do not assume that every plan allows the same appeal period.

If a payer is asking for money back, see our guide to 6 common recoupment dilemmas. Explore our dental insurance billing services (2.75% rate, $250 monthly minimum, 30-day free trial) for claims follow-up, payment posting and accounts receivable support. Contact eDental Billing to discuss your practice’s billing needs.

For related guidance, read what dental claim denials are and how to avoid them, review how the dental billing process works, or check our dental billing tips for practice teams.