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Revised 05.16.16

The Centers for Medicare & Medicaid Services (CMS) defines clerical errors (including minor errors or omissions) as human or mechanical errors on the part of the party or the contractor, such as:

  • Mathematical or computational mistakes
  • Transposed procedure or diagnostic codes
  • Inaccurate data entry
  • Misapplication of a fee schedule
  • Computer errors
  • Denial of claims as duplicates which the party believes were incorrectly identified as a duplicate
  • Incorrect data items, such as provider number, use of a modifier or date of service

If there is a medically denied line item on the claim, the Fiscal Intermediary Shared System (FISS) may not allow you to complete the adjustment electronically.

Beginning January 1, 2016, CMS implemented the automated Clerical Error Reopening (CER) process, which allows providers to perform reopenings electronically.

CGS encourages providers to use the CER process. Instructions for the process are communicated in articles:

If providers are unable to use the automated CER process, submit a hard copy adjustment using the Clerical Error Reopening Request FormPDF.

Note: Clerical errors or minor errors are limited to errors in form and content, which does not include failure to bill for certain items or services. CGS will not add items or services, based on a reopening request, that were not previously billed, with the exception of a few limited items that cannot be filed on a claim alone (e.g., HCPCS codes G0369, G0370, G0371 and G0374). Third party payer errors are not considered clerical errors.

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