Author: Jessica Sullivan, CPC
Remote Coder – Pinnacle Integrated Coding Solutions


(303) 801-0111


Modifier CS is used for the full reimbursement of COVID-19 testing visits from Medicare and private insurers. For services performed on March 18, 2020 through the end of the Public Health Emergency (“PHE”), physicians that bill to Medicare Part B should use the CS modifier to identify the service related to the cost-sharing waiver. These Medicare patients should NOT be charged any co-pays and/or deductible amounts for those services.

Under the Families First Coronavirus Response Act (FFCRA) and the Medicare and Medicaid Programs; Policy and Regulatory Revisions in Response to the COVID-19 Public Health Emergency Interim Final Rule, cost-sharing does not apply to the following reasons for medical visits: for services on or after date of service March 18, 2020 through the end of the PHE, the order or administration of a COVID-19 test and the related evaluation of the patient for the purpose of determining the need for such tests within the following categories of HCPCS E/M codes:

  • Office and other outpatient services
  • Hospital observation services
  • Emergency department services
  • Nursing facility services
  • Domiciliary, rest home, or custodial care services
  • Home services
  • Online digital evaluation and management services

For professional claims, physicians and practitioners who did not initially submit claims with the CS modifier must notify their Medicare Administrative Contractor (“MAC”) and request to resubmit applicable claims with dates of service on or after 3/18/2020 with the CS modifier to get 100% payment of the allowable cost for the service. For facility claims, those who did not initially submit claims with the CS modifier must resubmit applicable claims submitted on or after 3/18/2020, with the CS modifier to visit lines to get 100% payment.

Final tip: Both in-person and telehealth visits may have this modifier applied. It is recommended for telehealth services to have modifier 95 appended secondary to modifier CS, as 95 is informational and CS affects payment.  So, the coding would look as such: 99214-CS,95. Applying the appropriate diagnosis coding can further help to distinguish these services. The CDC has updated the ICD-10-CM coding and reporting guidelines to address COVID-19 diagnosis and exposure coding. Remember that while most payors usually follow Medicare guidelines, coding policies can vary from payer to payer.