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Billing code

G138A — Evoked potentials – upper or lower limbs – professional component

Limb evoked potentials, interpretation

Bill G138 for the professional component of upper or lower limb evoked potential testing; the technical component is G140.

Watch for: When only one limb is tested, bill G138 at 50%.

Code

G138A

Description

Evoked potentials – upper or lower limbs – professional component

FHO+ basket

Not in the FHO+ base rate basket (Schedule 2 or 2B).

Effective date

Apr 1, 2025

Termination date

No end date

Explanation

Updated October 26, 2026

Professional component of evoked potential testing of the upper or lower limbs.

What it covers

G138 is the professional component of evoked potentials of the upper or lower limbs. The technical component is G140 (J86).

The professional component covers supervision, monitoring where needed, and interpreting the results (J1).

Billing rules

• When only one limb is tested, bill G138 (or G140) at 50% (J86).
• You must personally interpret the results. Supervision and monitoring may be delegated to another physician (J1).

Often billed with

• G140 evoked potentials technical component (J86).

Related codes: G140, G415, G456, G457

Source: Schedule of Benefits (July 1, 2026), Diagnostic and Therapeutic Procedures, Neurology, Evoked Potentials, page J86.

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