Has Anyone Successfully Gotten Paid for the 3rd Level of Nerve Blocks or RFAs?
Getting paid for the 3rd level of nerve blocks or RFA is rare under Medicare. Its billing articles treat a third level…
Medical Billing 101 – Free Denial Code, CPT & RCM Guides
Find what a denial code means in plain English and the steps to fix it.
Most Used RCM & Denial Resolution Guides
- Appeal Letter Generator Build an editable payer appeal letter from the denial code, claim details and the arguments that fit.
- Timely Filing & Appeal Deadline Calculator Work out the claim, corrected claim or appeal deadline and how many days you have left.
- Denial Code Lookup (CARC & RARC) Find what a denial code means in plain English and the steps to fix it.
- CO-97 Bundling Denials: NCCI Edits and Modifiers Check the NCCI edit, decide whether modifier 59 or an X modifier applies, and correct or appeal.
- CO-16 Missing Information Denials Read the remark code, fix the missing or invalid claim data and resubmit.
- CO-29 Timely Filing Denials Prove the claim went out on time, or find the exception that lets you appeal.
- CO-50 Medical Necessity Denials Match the diagnosis to the coverage policy and build the records for an appeal.
- ER Visit Denied as Not an Emergency Use the prudent layperson rule to appeal an emergency room denial.
- About the Author: Manikandan J, CPC, CRCR Who writes and fact-checks these guides, with 10+ years in US revenue cycle management.
Free Billing Tools
Quick, free helpers for billers, coders and patients. No sign-up.
Appeal Letter Generator
Pick a denial code and payer, fill in claim details, copy a ready-to-edit appeal letter.
Timely Filing Deadline Calculator
Enter the date of service or EOB date to see claim and appeal deadlines.
Denial Code Lookup
Search any CARC/RARC (e.g. CO-97, CO-16) for its meaning and fix steps.
NPI Lookup
Search the CMS NPI Registry by NPI or name and state. See type, taxonomy and address.
Latest guides
The newest denial code explainers and billing updates.
CO-266 Denial Code (CARC 266) 2026: Compound Preparation Cost Adjustment
CO-265 Denial Code (CARC 265) 2026: Pharmacy Administrative Cost Adjustment
CO-264 Denial Code (CARC 264) 2026: Pharmacy Postage Cost Adjustment
PR-23 Denial Code (CARC 23) 2026: Prior Payer Impact Shown as Patient Share
PR-18 Denial Code (CARC 18) 2026: Duplicate Claim or Service as Patient Share
Has Anyone Successfully Gotten Paid for the 3rd Level of Nerve Blocks or RFAs?
Popular denial codes
- CO-16: Claim Lacks Information or Has a Billing Error
- CO-45: Charge Exceeds Fee Schedule or Contracted Amount
- CO-50: Not Deemed a Medical Necessity by the Payer
- CO-4: Modifier Inconsistent or Missing – Fix
- CO-22: Care May Be Covered by Another Payer (Coordination of Benefits)
- CO-29: The Time Limit for Filing Has Expired
- OA-18: Exact Duplicate Claim or Service
- CO-197: Precertification or Authorization Absent
- CO-18: Duplicate Claim With a CO Group
- CO-252: An Attachment or Other Documentation Is Required
- PR-1, PR-2 and PR-3: Deductible, Coinsurance and Copay (Patient Responsibility)
- CO-96: Non-Covered Charges – Causes & Fix
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Prior Authorization Denied? What to Do Next (MRI, Surgery or Medication)
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How to Read an Explanation of Benefits (and What to Do When Your Bill Doesn’t Match)
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Claim Denied as “Not Medically Necessary”? How to Appeal and Get an External Review
You can fight a “not medically necessary” denial, and you have more time and more rights than most people think. Ask your…