How to Reduce Claim Denials: 9 Practical Steps for Medical Practices

Every denied claim costs your practice twice: once in delayed revenue, and again in the staff time it takes to research, correct and resubmit it. Some denied claims are never reworked at all, which means that money is simply lost. The good news is that most denials follow predictable patterns, and predictable problems can be prevented.

This guide explains why claims get denied, how to read the denial codes on your remittance, and the practical steps that keep clean claims moving through the payer on the first pass.

Denied vs. rejected claims: know the difference

A rejected claim never entered the payer’s processing system. It failed a front-end check at the clearinghouse or payer because of a formatting problem, a missing field, or an invalid identifier such as an incorrect NPI. Rejected claims can usually be corrected and resubmitted quickly.

A denied claim was received and processed, and the payer decided not to pay it. Denials come back on your electronic remittance advice (ERA) or explanation of benefits (EOB) with reason codes, and they often need a corrected claim or a formal appeal. Tracking the two separately shows you whether your problem sits in claim preparation or in payer policy.

The most common reasons claims are denied

• Eligibility and coverage problems: the patient’s coverage ended, changed, or does not include the service.
• Missing or incorrect information: a misspelled name, wrong date of birth, or incorrect member ID.
• No prior authorization: the service required approval before it was performed.
• Coding errors: a diagnosis that does not support the procedure, a missing modifier, or an outdated code.
• Bundling edits: a procedure billed separately that the payer considers part of another service.
• Duplicate claims: the same service submitted more than once.
• Timely filing: the claim reached the payer after its filing deadline.

Reading the denial codes on your ERA

Payers explain denials with Claim Adjustment Reason Codes (CARCs), often paired with Remittance Advice Remark Codes (RARCs) that add detail. A few you will see often:

• CO-16: the claim lacks information needed for adjudication. Check the remark code to see exactly what is missing.
• CO-27: services were provided after the patient’s coverage ended.
• CO-29: the time limit for filing has expired.
• CO-97: the service is included in the payment for another service or procedure.
• CO-197: precertification or authorization was absent.
• CO-50: the payer does not consider the service medically necessary.

The group code in front matters too. CO (contractual obligation) means the provider generally cannot bill the patient for that amount, while PR (patient responsibility) means the balance can be billed to the patient.

9 practical steps to reduce claim denials

1. Verify eligibility before every visit

Coverage changes more often than most practices expect, especially at the start of a year and after job changes. Check eligibility and benefits before each appointment, not only at the first visit, and confirm the plan covers the planned service at your location.

2. Capture accurate patient information at registration

Scan the insurance card front and back, confirm the patient’s legal name and date of birth, and record the subscriber details exactly as they appear on the card. Small typing errors at the front desk are one of the easiest denials to prevent.

3. Build a prior authorization checklist

Keep an up-to-date list of the services that need authorization for each of your top payers. Record the authorization number, approved dates and approved units, and make sure the claim matches them.

4. Code to the documentation

The claim must be supported by the provider’s notes. Make sure diagnosis codes are specific, support medical necessity for each procedure, and that modifiers are used correctly. Regular internal coding reviews catch patterns before a payer does.

5. Scrub every claim before submission

Claim scrubbing software checks for missing fields, invalid code combinations and payer-specific edits before the claim leaves your office. A clean claim that is paid on the first pass is always cheaper than a claim that needs rework.

6. Track timely filing limits by payer

Filing deadlines vary widely. Medicare generally requires claims to be filed within 12 months of the date of service, while many commercial plans allow far less time. Submit claims within days of the visit and monitor unacknowledged claims so nothing ages past the deadline.

7. Work denials quickly and by category

Group denials by reason code and payer rather than working them one at a time. A single root cause, such as a missing modifier for one payer, can be fixed once and prevent hundreds of future denials.

8. Appeal with a clear, documented argument

When a denial is wrong, appeal it. Include the claim details, the reason you disagree, supporting medical records, and the payer’s own policy language where it helps. Watch appeal deadlines: for Medicare, a redetermination request must generally be filed within 120 days of receiving the initial determination.

9. Measure and report every month

Track your denial rate, first-pass acceptance rate, days in A/R and the top denial reasons by payer. What gets measured gets fixed, and monthly reporting shows whether your changes are working.

When to get help

If your team spends more time reworking claims than submitting them, or if the same denial reasons keep returning, it may be time for a specialist. The DocMBS team handles eligibility checks, coding, claim scrubbing, denial management and appeals for US practices. You can explore our medical billing services or book an appointment with our billing team to talk through your practice’s denial patterns.