CurrentColorado Rocky Mountain Health PlansPolicy 2026R5011B

Maximum Frequency per Day (MFD) for outpatient hospital services

Defines maximum reimbursable units per CPT/HCPCS code for outpatient hospital claims billed on UB04 (or electronic equivalent) across UnitedHealthcare Commercial and Individual Exchange plans; applies to all network and non‑network outpatient facility claims.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyMaximum Frequency per Day (MFD) for outpatient hospital services

Policy CodePolicy 2026R5011B

Change TypeNo material change

Effective Date

Next Review Date

Key ActionWhen units exceed the established MFD, report an appropriate modifier (59, 76, 91, XE, XP, XS, or XU) to allow consideration for additional reimbursement without attaching medical records to the claim.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

Quarterlyupdate cadence for MFD values

No overrideCMS MAI 2 adjudication stance

UB04forms covered

59,76,91,XE,XP,XS,XUaccepted override modifiers

Maximum Frequency per Day (MFD) Coverage Criteria

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MFD reimbursement criteria

Reimbursement is allowed up to the MFD; exceptions and adjudication rules apply as follows.

Units billed on the same date of service for the same CPT/HCPCS code are reimbursable up to and including the Maximum Frequency per Day (MFD) value.

EXCEPTION - Modifier-based consideration

When units exceed the established MFD and are reported with an appropriate modifier (59, 76, 91, XE, XP, XS, or XU), additional reimbursement may be considered.
Medical records are not required to be submitted with the claim when these modifiers are appropriately reported; however, documentation in the medical record should reflect and support the modifier use and the number of units reported.

HARD LIMIT - MAI 2 adjudication

For CPT/HCPCS codes assigned a CMS MAI indicator of '2', units in excess of the MFD will not be reimbursed.
Per CMS guidelines, no modifier override will be allowed for MAI 2 codes; anatomic modifiers may be considered when appropriate.

If an MFD value is not listed for a code, it is the responsibility of the outpatient hospital to bill the appropriate number of units for each service.

Code Assignments and MUE Alignment

MFD code assignmentsmixed

Maximum Frequency per Day (MFD) assignments for CPT and HCPCS codes per policy and CMS MUE guidance

Use of CMS MUE/Facility Outpatient MUE table

Source for MFD valuesMFD values align with the CMS MUE table for Facility Outpatient Hospital Services (CMS MUE) — CMS MUE table is the primary source for MFD assignments.

Codes with CMS MUE = 0Codes assigned a CMS MUE value of zero will have MFD values established using the same CMS criteria (anatomic considerations, code descriptors, CPT instructions, nature of service/analyte/equipment, unlikely clinical treatment).

Quarterly reviewMFD values are evaluated and/or updated quarterly to reflect new, changed, and deleted codes.

Modifier and Adjudication Rules for Providers

Prior Authorization

Report accepted modifiers to request reimbursement above the MFD

When units billed for the same CPT/HCPCS code on a single date of service exceed the established MFD, UnitedHealthcare may consider additional reimbursement if the claim reports an appropriate modifier (59, 76, 91, XE, XP, XS, or XU). Medical records do not need to be submitted with the claim when one of these modifiers is appropriately reported, but the medical record must reflect and support the modifier use and the number of units reported.

Acceptable modifiers: 59, 76, 91, XE, XP, XS, XU
No claim-attached medical record required when modifier is properly reported
Documentation in the medical record must support the modifier and units billed

Denial Risk

MAI 2 codes — excess units are not reimbursable; no modifier override

For CPT/HCPCS codes assigned a MAI indicator of '2', UnitedHealthcare will not reimburse units in excess of the MFD and will not allow a modifier override; anatomic modifiers may be considered when appropriate.

MAI 2 codes: excess units considered impossible and are non‑reimbursable
No modifier can be used to override the MAI 2 adjudication (except possible anatomic modifiers per CMS guidance)

Key Definitions

Units

DefinitionUnits = the number of times services with the same CPT or HCPCS codes are provided per day by the same outpatient hospital.

Claim presentationApplies whether the hospital submits multiple units on one claim line or multiple claim lines with one or more units each.

PurposeUsed to limit reimbursement for obvious billing submission errors, incorrect coding, or unlikely clinical treatment.

Maximum Frequency per Day (MFD)

DefinitionMaximum Frequency per Day (MFD) = the highest number of units eligible for reimbursement of services on a single date of service for an individual CPT or HCPCS code; determined using CMS MUE values and clinical/anatomic considerations.

Determination sourcesMFDs are set using CMS MUE values (Facility Outpatient MUE table) and additional criteria such as CPT/HCPCS descriptors, CPT coding instructions, and anatomic/clinical considerations.

Provider responsibilityIf an MFD value is not listed for a code, the outpatient hospital is responsible to bill the appropriate number of units.

MAI 2

MAI 2 ruleFor CPT/HCPCS codes assigned MAI indicator '2', units in excess of the MFD (CMS MUE) will not be reimbursed; such excess units are considered impossible per CMS guidance.

Modifier overridePer CMS guidelines, no modifier override will be allowed for MAI 2 codes; anatomic modifiers may be considered when appropriate.

Adjudication stanceUnitedHealthcare will not allow reimbursement for units above the MFD for codes with MAI 2.