CurrentColorado Rocky Mountain Health PlansPolicy 2026R5000C

Assistant-at-Surgery reimbursement on CMS 1500

This policy governs reimbursement for Assistant-at-Surgery services billed on the CMS-1500 (or electronic equivalent) for UnitedHealthcare Commercial products and applies to all network and non-network physicians and qualified health care professionals.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyAssistant-at-Surgery reimbursement on CMS 1500

Policy CodePolicy 2026R5000C

Change TypeAttachments revisedclarifying and application updates

Effective Date

Next Review Date

Key ActionSubmit claims on CMS-1500 (or electronic equivalent) with accurate coding and the appropriate Assistant Surgeon modifier (80/81/82 or AS) to request reimbursement.

SourceLink

POLICY UPDATE CHANGES

Attachments section updated to revise the Assistant-at-Surgery Eligible List.

Q&A #6 added clarifying that codes not on the CMS NPFS may be added to the policy if deemed appropriate.

Application section updated to state applicability to all products and all network and non-network Physicians and QHPs.

16%Physician assistant reimbursement

14%Health Care Professional reimbursement

1Assistants allowed per procedure

NPFS '2'CMS indicator used

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Assistant-at-Surgery Coverage Criteria

Assistant-at-Surgery coverage criteria

Assistant-at-Surgery services are reimbursable only when ALL of the following criteria are met:

ALL of the following

Procedure code is included on UnitedHealthcare's Assistant-at-Surgery Eligible List based on CMS NPFS indicator '2', or UnitedHealthcare has added the code to the Eligible List after review.
The Assistant-at-Surgery submits the identical procedure code(s) as the primary surgeon.

Modifier requirements depend on assistant type

Physician assistant (MD/DO): Physicians assisting at surgery must report one of modifiers 80, 81, or 82 when submitting the identical procedure code(s).
Health Care Professionals (e.g., physician assistants, clinical nurse specialists, nurse practitioners without MD/DO) must report modifier AS when submitting the identical procedure code(s).

Only one Assistant-at-Surgery is reimbursable per procedure; multiple assistants are not paid (maximum assistants per procedure = 1).

Reimbursement rates: Physicians (MD/DO) assisting at surgery are reimbursed at 16% of the Allowable Amount; Health Care Professionals assisting at surgery are reimbursed at 14% of the Allowable Amount.

For cesarean deliveries, only non-global cesarean section delivery codes (without antepartum or postpartum components) are reimbursable when submitted with an appropriate Assistant Surgeon modifier. Global cesarean CPT codes 59510, 59515, 59618, and 59622 submitted by an Assistant-at-Surgery will be reimbursed using non-global codes 59514 or 59620 (59510 -> 59514; 59515 -> 59514; 59618 -> 59620; 59622 -> 59620).

Surgical technicians are not eligible to report modifier AS; their services are included in facility reimbursement and are not separately reimbursable.

UnitedHealthcare may consider additional factors (legislative mandates, contractual obligations, member benefits) and may add codes not listed on the CMS NPFS to the Eligible List at its discretion; such determinations supersede or modify reimbursements as applicable.

If multiple procedure codes are submitted by an Assistant-at-Surgery, multiple procedure reductions will apply as applicable.

Codes, Limits, and Reimbursement

Maximum assistants per procedure

Maximum assistants per procedureOne assistant-at-surgery per operative procedure is reimbursable unless otherwise specified by state mandate or facility contract.

Physician assistant reimbursement percentage

Physician assistant reimbursement percentage16% of the Allowable Amount for eligible surgical procedures (based on CMS).

Health Care Professional reimbursement percentage

Health Care Professional reimbursement percentage14% of the Allowable Amount for eligible surgical procedures (based on CMS).

Claims Submission, Billing Rules, and Exclusions

Billing Rule

Claims submission and modifier use

Submit claims on the CMS-1500 (or electronic equivalent) and ensure the assistant-at-surgery reports the identical procedure code(s) as the primary surgeon using the appropriate Assistant Surgeon modifier: physicians (MD/DO) use modifiers 80, 81 or 82; Health Care Professionals use modifier AS.

Claims must be submitted on the CMS-1500 form or its electronic equivalent.
Assistant must report the identical procedure code(s) as the primary surgeon and use the correct modifier (80/81/82 for physicians; AS for Health Care Professionals).

Billing Rule

Cesarean section billing rule

For cesarean deliveries, submit a non-global cesarean section delivery code (without antepartum or postpartum components) with the appropriate Assistant Surgeon modifier; if a global cesarean CPT code (59510, 59515, 59618, 59622) is submitted by an Assistant-at-Surgery it will be reimbursed using the mapped non-global codes (59514 or 59620) as specified.

Key Definitions

Allowable Amount

DefinitionAllowable Amount: dollar amount eligible for reimbursement to the Physician or other Qualified Health Care Professional on the claim (often called allowed amount or eligible expense).

Assistant-at-Surgery capThe Allowable Amount for Assistant-at-Surgery services is no more than the Allowable Amount payable to the primary surgeon for the covered services assisted.

UsageUsed as the base to calculate Assistant-at-Surgery reimbursement percentages (16% for Physicians, 14% for Health Care Professionals).

Assistant-at-Surgery

DefinitionAssistant-at-Surgery/Assistant Surgeon: A Physician or other Qualified Health Care Professional who is assisting the Physician performing a surgical procedure.

Billing requirement

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyAssistant-at-Surgery reimbursement on CMS 1500

Policy CodePolicy 2026R5000C

Change TypeAttachments revisedclarifying and application updates

Effective Date

Next Review Date

Key ActionSubmit claims on CMS-1500 (or electronic equivalent) with accurate coding and the appropriate Assistant Surgeon modifier (80/81/82 or AS) to request reimbursement.

SourceLink

On This Page

59510 or 59515 submitted by an Assistant-at-Surgery will be reimbursed as 59514.
59618 or 59622 submitted by an Assistant-at-Surgery will be reimbursed as 59620.

Denial Risk

Surgical technician exclusion

Do not submit surgical technician services separately with modifier AS; per CMS claims processing guidance, surgical technicians are not eligible to report modifier AS and their services are included in facility reimbursement and are not separately reimbursable.

Surgical technicians are not listed as practitioners who can report modifier AS per CMS guidance.
Services of a surgical technician assisting at surgery are included in facility reimbursement and will not be reimbursed separately.

Assistant must submit the identical procedure code(s) as the primary surgeon when seeking reimbursement.

Applicable modifiersPhysicians use modifiers 80/81/82; Health Care Professionals use modifier AS.

Health Care Professional

DefinitionHealth Care Professional: a physician assistant, clinical nurse specialist or nurse practitioner who does not have an MD or DO degree.

Reimbursement percentageWhen eligible, reimbursed at 14% of the Allowable Amount.

ModifierShould report services with modifier AS when assisting at surgery.

Physician

DefinitionPhysician: a Doctor of Medicine (MD) or Doctor of Osteopathy (DO).

Reimbursement percentageWhen providing Assistant-at-Surgery services, Physicians are reimbursed at 16% of the Allowable Amount.

ModifiersPhysician assistants-at-surgery should report with modifier 80, 81 or 82 when applicable.

Same Individual Physician or QHCP

DefinitionSame Individual Physician or Other Qualified Health Care Professional: the same individual rendering health care services reporting the same Federal Tax Identification number.

ImplicationDefines identity for billing when the same individual reports services on a claim.

Use in policyUsed to determine when services are from the same provider vs. separate practitioners for reimbursement decisions.