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Billing code

G418A — Routine Eeg - Professional Component (16 - 21 Channel Eeg)

Routine EEG interpretation, 16–21 channels

Bill G418 for supervising and personally interpreting a routine EEG recorded with 16 to 21 channels.

Watch for: Only one of G415, G418, G543 or G496 is payable per day, and no EEG is payable with a sleep study.

Code

G418A

Description

Routine Eeg - Professional Component (16 - 21 Channel Eeg)

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 a routine EEG done with 16 to 21 channels: supervising and interpreting the recording.

What it covers

G418 is the routine EEG professional component listed for a 16–21 channel EEG (J84). A routine EEG is at least a 20-minute recording with referential and bipolar montages and at least 8 channels (except in neonates). Hyperventilation and photic stimulation should be done whenever clinically possible (J84).

The professional component covers supervision, monitoring where needed, and interpreting the results (J1). The technical component is G414 (J84).

Billing rules

• Only one of G415, G418, G543 or G496 is payable per day (J84).
• No EEG service is payable with an overnight or daytime sleep study (J898, J899, J990, J896, J897, J895, J890, J889, J893 or J894) (J84).
• A sleep-deprived/induced EEG or video EEG that doesn't meet its requirements is paid as a routine EEG (G414 and G415/G418) (J84).
• Prolonged EEG monitoring (G545) is paid at nil when claimed with any baseline EEG (J85).
• You must personally interpret the results. Supervision and monitoring may be delegated to another physician (J1).

Often billed with

• G414 routine EEG technical component (J84).
• G546 radiotelemetry or portable recording professional component (J85).

Common rejections

• ADH: OHIP describes this as 'Cannot be billed together': only one of G415, G418, G543 or G496 is payable per day (J84).

Related codes: G414, G415, G543, G496, G546

Source: Schedule of Benefits (July 1, 2026), Diagnostic and Therapeutic Procedures, Neurology, Electroencephalography, page J84.

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