Modifier 63; Procedure Performed on Infants Less Than 4 kg

Policy No: 110
Originally Created: 09/01/2009
Section: Modifiers
Last Reviewed: 02/01/2024
Last Revised: 02/01/2024
Approved: 02/08/2024
Effective: 03/01/2024

This policy applies only to physicians and other qualified health care professionals.

Modifier 63 - Procedure performed on infants less than 4kg
Current Procedural Terminology (CPT©) modifier 63 represents procedures performed on neonates and infants up to a present body weight of 4kg.

There is a significant increase in work intensity for procedures performed on infants less than 4kg related to temperature control, obtaining IV access, and the operation itself, which is technically more difficult regarding to maintenance of homeostasis. The submission of modifier 63 on an appropriate CPT code indicates that the infant's weight is under 4kg at the time the service is rendered, and this low weight resulted in increased work or complexity of work.

Unless otherwise designated below, modifier 63 is valid with:

• CPT codes 20100-69990, with exception to modifier 63 exempt codes.
• Medicine/Cardiovascular codes 92920, 92928, 92953, 92960, 92986, 92987, 92990, 92997, 92998, 93312, 93313, 93314, 93315, 93316, 93317, 93318, 93452, 93505, 93563, 93564, 93568, 93569, 93573, 93574, 93575, 93580, 93581, 93582, 93590, 93591, 93592, 93593, 93594, 93595, 93596, 93597, 93598, 93615, 93616.

Therefore, modifier 63 is not valid with evaluation and management services, anesthesia, radiology, pathology/laboratory, or medicine codes (other than those listed above).

Medical records may be requested for review to support the additional payment. Documentation from the patient's record must indicate the significantly greater effort required and the reason for the additional work which may include, but not be limited to, increased intensity or time, technical difficulty of procedure that is not described by a more comprehensive procedure code, severity of the patient's condition, or increased physical and mental effort.

The codes in the following table are modifier 63 exempt (Do not append modifier 63):

When a provider reports an eligible procedure or service with modifier 63 appended, reimbursement will be 120% of the established fee.

Modifiers 63 and 22 cannot be billed on the same code.

American Medical Association. Appendix A: Modifiers, CPT©, Chicago, AMA Press.

American Medical Association. Appendix F: Summary of CPT Codes Exempt from Modifier 63. CPT©, Chicago, AMA Press.

Modifier 22; Increased Procedural Services