CurrentAnthemPolicy G-07022

Modifiers LT and RT: Left-Side and Right-Side Procedures

Defines Anthem Wisconsin reimbursement stance for use of modifiers LT and RT to indicate left- or right-side procedures and how they affect reimbursement and billing for BadgerCare Plus and Medicaid SSI members.

Policy Summary

PayerAnthem

PolicyModifiers LT and RT: Left-Side and Right-Side Procedures

Policy CodePolicy G-07022

Change TypeNo material change

Effective DateJul 21, 2025

Next Review Date

Key ActionAppend LT or RT only to indicate left or right procedures; services must meet authorization and medical necessity requirements.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

BadgerCare Plus & Medicaid SSI (WI)Applies to

100%Reimbursement basis

1Informational modifiers

ApplyMultiple surgery rules

Coverage Criteria - Modifiers LT/RT

Modifiers LT/RT Coverage Criteria

Coverage and billing stance for modifiers indicating laterality:

Modifiers LT and RT may be appended to procedure codes to indicate left- or right-sided items, supplies, or procedures.

Reimbursement is based on 100% of the fee schedule or contracted/negotiated rate; modifiers LT and RT are informational and do not increase or decrease the payment amount.

Do not append modifier LT or RT to procedure codes that are described as bilateral or to codes that indicate bilateral procedures; LT/RT do not indicate bilateral services.

When both LT and RT are used to indicate that surgical procedures were performed on each side, claims are subject to multiple surgery rules.

Services must meet any applicable provider, state, federal, or CMS contract requirements and must meet authorization and medical necessity guidelines as appropriate.

Policy Summary

PayerAnthem

PolicyModifiers LT and RT: Left-Side and Right-Side Procedures

Policy CodePolicy G-07022

Change TypeNo material change

Effective DateJul 21, 2025

Next Review Date

Key ActionAppend LT or RT only to indicate left or right procedures; services must meet authorization and medical necessity requirements.

SourceLink

On This Page

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Provider Actions — Authorization, Billing Impact, and Documentation

Prior Authorization

Authorization and Medical Necessity

Services must meet authorization and medical necessity guidelines appropriate to the procedure and diagnosis; claims and reimbursement are subject to authorization and medical necessity review and must be supported in the medical record or office notes.

Use proper billing and submission guidelines and industry-standard, compliant codes (CPT, HCPCS, revenue codes).
Services billed must be fully supported in the medical record and/or office notes.

Billing Rule

Modifier Billing Impact (LT/RT)

Modifiers LT and RT are informational and do not change the payment amount; when both sides are billed indicating procedures on left and right, claims may be subject to multiple surgery rules.

Reimbursement is based on 100% of the fee schedule or contracted/negotiated rate; LT/RT do not increase or decrease reimbursement.
Do not append LT or RT to procedure codes that are described as bilateral or that already indicate laterality.
When LT and RT both indicate procedures were performed on each side, multiple surgery rules apply.

Definitions — Laterality and Procedure Terms

Bilateral — definition

DefinitionBilateral procedures are performed on both sides of the body during the same operative session.

Billing implicationDo not use LT or RT to report bilateral procedures; claims for procedures performed on both sides are subject to multiple surgery rules when both sides are billed.

ExampleIf the procedure was performed on both left and right sides during the same session, report per bilateral coding guidance rather than appending LT and RT to a single bilateral code.

Modifier LT — definition

DefinitionModifier LT identifies procedures performed on the left side of the body.

PurposeUsed to indicate left-sided services; informational only and does not change reimbursement amount.

RestrictionDo not append LT to codes that are described as bilateral or inherently indicate laterality/bilateral status.

Modifier RT — definition

DefinitionModifier RT identifies procedures performed on the right side of the body.

PurposeUsed to indicate right-sided services; informational only and does not change reimbursement amount.

RestrictionDo not append RT to codes that are described as bilateral or inherently indicate laterality/bilateral status.

Unilateral — definition

DefinitionUnilateral procedures are performed on one side of the body.

Coding noteUse LT or RT to report unilateral procedures to indicate the side of service; modifiers are informational and do not change payment.

DistinctionDo not confuse unilateral with bilateral — unilateral codes should not be billed with LT/RT if the code description already specifies laterality or bilateral performance.

OpenPayer

Modifiers LT and RT: Left-Side and Right-Side Procedures

Coverage Criteria - Modifiers LT/RT

Coding — Modifiers and Appropriate Use

Provider Actions — Authorization, Billing Impact, and Documentation

Definitions — Laterality and Procedure Terms

LT	Modifier indicating left side
RT	Modifier indicating right side