QSHCPCS Level II

Monitored anesthesia care service

Usage notes
Append to report that a service was a monitored anesthesia care (MAC) service.
Common mistakes
Omitting QS on a MAC case, causing the payer to process it as general anesthesia and apply the wrong payment methodology.

Related modifiers

Frequently asked questions

What does modifier QS mean?

Monitored anesthesia care service

When do I use modifier QS?

Append to report that a service was a monitored anesthesia care (MAC) service.

What's a common mistake with modifier QS?

Omitting QS on a MAC case, causing the payer to process it as general anesthesia and apply the wrong payment methodology.

HCPCS modifier data from CMS. CPT® is a registered trademark of the American Medical Association — CPT modifier descriptions are not included on this site. Always verify codes with authoritative sources before making billing decisions.