Health insurance appeal guides

Plain-language guides to appealing a denied US health insurance claim: what 63 denial reason codes and 9 remark codes mean, appeal steps and deadlines for 9 kinds of plan, and free help in all 50 states, DC and Puerto Rico.

Jump to: Plan types · Denial codes · Remark codes · States

Appeal steps and deadlines by plan type

• Most private plans
• Marketplace and individual plans
• Job-based plans
• Fully insured job-based plans
• Self-funded job-based plans (ERISA)
• Original Medicare
• Medicare Advantage
• Medicare Part D drug plans
• Medicaid and CHIP

Denial codes on an Explanation of Benefits

The number is the reason. The letters in front (CO, PR, OA or PI) say who the plan thinks owes the amount.

Coverage decisions you can appeal

• CO-39: denied when authorization was requested
• CO-40: not an emergency or urgent care
• CO-49: routine or preventive care not covered
• CO-50: not medically necessary
• CO-51: pre-existing condition
• CO-55: experimental or investigational
• CO-56: treatment not proven to work
• CO-96: non-covered charge
• CO-119: benefit limit reached
• CO-150: records don't support the level of service
• CO-151: records don't support this many services
• CO-167: diagnosis not covered
• CO-197: prior authorization missing
• CO-198: more done than was authorized
• PR-204: not covered under your plan benefits
• CO-222: more hours, days or units than allowed
• CO-242: out-of-network provider
• CO-243: not authorized by network or primary doctor
• CO-273: coverage limit or guideline exceeded
• CO-284: authorization doesn't cover these services
• CO-288: missing referral

Billing problems the provider fixes

• CO-4: procedure code and modifier mismatch
• CO-5: service does not match place of service
• CO-6: service does not fit patient's age
• CO-7: service does not fit patient's sex
• CO-8: service does not fit provider specialty
• CO-9: diagnosis does not fit patient's age
• CO-11: diagnosis does not support the service
• CO-15: missing or invalid authorization number
• CO-16: missing information or billing error
• OA-18: duplicate claim or service
• CO-24: managed care payment arrangement
• CO-29: claim filed after the deadline
• CO-31: patient not matched to a member
• CO-58: care given in the wrong setting
• CO-97: bundled with another service
• CO-107: related claim or service not found
• CO-109: sent to the wrong insurer
• CO-140: patient name and member ID don't match
• CO-146: diagnosis code not valid on that date
• CO-170: provider type can't bill this service
• CO-181: service code not valid on that date
• CO-182: modifier not valid on that date
• CO-185: treating provider not eligible
• CO-199: revenue code and service code mismatch
• CO-226: plan didn't get info from the provider
• CO-234: not paid separately
• CO-236: coding combination not allowed
• CO-252: more documents needed
• CO-256: not payable under managed care contract

Codes that need something from you

• CO-19: workers' compensation should pay
• CO-22: another insurance should pay first
• CO-26: care before coverage started
• CO-27: care after coverage ended
• CO-177: eligibility rules not met
• CO-227: plan didn't get info from you

Adjustments, not denials

• PR-1: deductible amount
• PR-2: coinsurance amount
• PR-3: copay amount
• OA-23: another insurer already paid part
• CO-45: charge above the allowed amount
• CO-59: several procedures on the same day
• CO-253: Medicare sequestration cut

Remark codes

• N130: based on your plan's benefit terms
• M127: medical records missing
• N290: treating provider details missing
• MA130: incomplete claim, must be resubmitted
• N362: more units than the maximum
• N386: Medicare national coverage policy
• N115: local Medicare coverage policy
• N30: patient not eligible on that date
• N425: excluded by law from coverage

Appeal rights and free help by state

• Alabama
• Alaska
• Arizona
• Arkansas
• California
• Colorado
• Connecticut
• Delaware
• District of Columbia
• Florida
• Georgia
• Hawaii
• Idaho
• Illinois
• Indiana
• Iowa
• Kansas
• Kentucky
• Louisiana
• Maine
• Maryland
• Massachusetts
• Michigan
• Minnesota
• Mississippi
• Missouri
• Montana
• Nebraska
• Nevada
• New Hampshire
• New Jersey
• New Mexico
• New York
• North Carolina
• North Dakota
• Ohio
• Oklahoma
• Oregon
• Pennsylvania
• Puerto Rico
• Rhode Island
• South Carolina
• South Dakota
• Tennessee
• Texas
• Utah
• Vermont
• Virginia
• Washington
• West Virginia
• Wisconsin
• Wyoming

General information, not legal or medical advice. Rules differ by plan and state, so check the dates and instructions on your own denial notice, and talk to your doctor about the medical side. Free help is available from your state and the contacts listed.