CurrentHumanaPolicy CP2015006

Inpatient to Outpatient Rebilling

Defines Humana Medicare Advantage billing and reimbursement requirements when an inpatient admission is determined not medically necessary and how providers must rebill services as outpatient or Part B claims; applies to providers billing Humana Medicare Advantage plans.

Policy Summary

PayerHumana

PolicyInpatient to Outpatient Rebilling

Policy CodePolicy CP2015006

Change TypeNo material change

Effective Date

Next Review Date

Key ActionIf an acute care hospital determines before discharge that inpatient care was not appropriate, submit services on an outpatient TOB 13x or 85x claim and include condition code 44.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

condition code 44 requiredbilling requirement for outpatient rebilling

report W2billing requirement for post-discharge conversions

Member pays cost sharingmember financial responsibility

CMS Part B guidanceregulatory alignment

Billing and Reimbursement Criteria

Billing and reimbursement criteria

Procedures for billing when inpatient admission is determined not medically necessary:

If an acute care hospital determines before discharge that the patient should not have been admitted as an inpatient, the provider must submit services on an appropriate outpatient TOB 13x or 85x claim, include condition code 44, may submit all codes appropriate for that outpatient TOB, and must not submit an inpatient claim.

If the determination is made after discharge that the patient should not have been admitted as an inpatient, the provider must submit an inpatient Part B TOB 12x claim reflecting reasonable and necessary Part B services with correct CPT/HCPCS codes when available, report condition code W2 to indicate a Part B claim, and include 'A/B Rebilling' in the treatment authorization field.

For preadmission services in the 3‑day payment window, the hospital may separately bill services provided prior to the inpatient admission on an appropriate outpatient TOB 13x or 85x claim and should report 'A/B Rebilling' in the treatment authorization field of that outpatient claim.

Policy Summary

PayerHumana

PolicyInpatient to Outpatient Rebilling

Policy CodePolicy CP2015006

Change TypeNo material change

Effective Date

Next Review Date

Key ActionIf an acute care hospital determines before discharge that inpatient care was not appropriate, submit services on an outpatient TOB 13x or 85x claim and include condition code 44.

SourceLink

On This Page

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Required Claim Types, Condition Codes, and Payment Window

Required claim types and condition codesmixed

Condition code 44	Used on outpatient claims when physician ordered inpatient services but internal review determined inpatient criteria not met.
Condition code W2	Indicates conversion of an inpatient claim to an outpatient (Part B) claim after discharge.
TOB 13x or 85x	Appropriate outpatient type of bill codes to submit when inpatient admission determined not appropriate prior to discharge.
TOB 12x	Inpatient Part B type of bill to submit when determination after discharge that patient should not have been admitted; report 'A/B Rebilling' in treatment authorization field.

3-day payment window (inv-03)

SummaryServices provided prior to an inpatient admission may be separately billed within the 3-day payment window; hospital should report 'A/B Rebilling' in the treatment authorization field of the appropriate outpatient TOB 13x or 85x claim.

When to applyFor preadmission services rendered before an inpatient admission that fall within the CMS 3-day payment window.

Related claim typesAppropriate outpatient TOB 13x or 85x claim used to bill these preadmission services.

Member cost sharingMember's hospital outpatient cost sharing applies to outpatient/Part B claims for these services.

Authorization and Denied Inpatient Authorizations

Denial Risk

Provider action: Authorization and denied inpatient authorizations

If an inpatient admission is determined not to be medically necessary, providers must follow CMS guidance for Part B rebilling. Before discharge: submit services on an appropriate outpatient TOB 13x or 85x claim, include all outpatient-appropriate codes, and report condition code 44. Do not submit an inpatient claim. After discharge: submit services on an inpatient Part B TOB 12x claim with the reasonable and necessary Part B services and correct CPT/HCPCS codes. Report condition code W2 to indicate a Part B claim and include "A/B Rebilling" in the treatment authorization field. For preadmission services within the 3-day payment window, bill those services separately on the appropriate outpatient TOB 13x or 85x claim and report "A/B Rebilling" in the treatment authorization field.

Before discharge: use outpatient TOB 13x or 85x; report condition code 44; do not submit an inpatient claim.
After discharge: use inpatient Part B TOB 12x; report condition code W2; include "A/B Rebilling" in treatment authorization field; report correct CPT/HCPCS codes.
Preadmission (3-day window): separately bill preadmission services on outpatient TOB 13x or 85x and include "A/B Rebilling".
If a required inpatient authorization was not obtained or was denied, facilities must bill emergency-related services provided before the inpatient admission separately from inpatient services. Humana will deny inpatient claims that include unauthorized inpatient services, including charges for preadmission emergency-related services.
Some services billed on inpatient Part B or outpatient claims may require specific authorization — verify prior authorization requirements before billing.

Key Terms and Codes

Appropriate outpatient TOB 13x or 85x (inv-05)

DefinitionA claim submitted with a type of bill code that a particular acute care hospital is permitted to use in ASC X12 835I transactions for outpatient services or applicable UB04 equivalent.

When requiredUsed when an acute care hospital determines before discharge that inpatient level of care was not appropriate and services must be submitted as outpatient.

Acceptable TOBsTOB 13x or 85x for outpatient rebilling as specified by the hospital's permitted outpatient billing codes.

Related requirementsInclude condition code 44 on the outpatient claim when pre-discharge determination is made.

Condition code 44 (inv-06)

DefinitionA condition code used on outpatient claims only when the physician ordered inpatient services but, upon internal utilization review performed before the claim was originally submitted, the hospital determined that the services did not meet inpatient criteria.

Use caseReport on outpatient TOB 13x or 85x claims when the decision that inpatient admission was not appropriate is made prior to discharge.

EffectSignals that services originally intended as inpatient are billed as outpatient due to pre-discharge determination; an inpatient claim should not be submitted.

Condition code W2 (inv-07)

DefinitionA condition code that indicates a conversion of an inpatient claim to an outpatient claim after discharge.

Use caseReport condition code W2 on an inpatient Part B TOB 12x claim when determination after discharge shows the patient should not have been admitted as an inpatient.

Additional requirementInclude 'A/B Rebilling' in the treatment authorization field to indicate Part B rebilling.

Payment window (3-day payment window) (inv-08)

DefinitionPeriod of time in which rendered services must, as required by the Centers for Medicare & Medicaid Services (CMS), be bundled with the inpatient claim.

3-day applicationFor preadmission services in the 3-day payment window, a hospital may separately bill services provided prior to an inpatient admission on an appropriate outpatient TOB 13x or 85x claim and should report 'A/B Rebilling' in the treatment authorization field.

ImplicationServices falling within this payment window are otherwise subject to bundling with the inpatient admission unless properly rebilled per policy.

Regulatory basisDefined consistent with CMS requirements for payment windows and bundling of preadmission services.