Modifier AD — Medical supervision by a physician: more than four concurrent anesthesia

ADHCPCS Level II

Medical supervision by a physician: more than four concurrent anesthesia

Usage notes: Append to an anesthesia code when a physician medically supervises more than four concurrent anesthesia procedures.
Common mistakes: Using AD for 2-4 concurrent cases — that's medical direction (QK), a different billing scenario with different payment rules than AD's supervision-only scenario.

Related modifiers

A1Dressing for one wound A2Dressing for two wounds A3Dressing for three wounds A4Dressing for four wounds A5Dressing for five wounds A6Dressing for six wounds A7Dressing for seven wounds A8Dressing for eight wounds

Frequently asked questions

What does modifier AD mean?

Medical supervision by a physician: more than four concurrent anesthesia

When do I use modifier AD?

Append to an anesthesia code when a physician medically supervises more than four concurrent anesthesia procedures.

What's a common mistake with modifier AD?

Using AD for 2-4 concurrent cases — that's medical direction (QK), a different billing scenario with different payment rules than AD's supervision-only scenario.

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.