What are the billing rules for E401C?

Based on when the case commences: a case that starts before midnight takes E400, even if it runs past 00:00 (GP87, GP94). For the assistant (B suffix) and anaesthetist (C suffix) only. The surgeon's night premium on the procedural fee is E410, which has its own criteria (GP87, GP94, GP103 to GP104). A replacement assistant (E005B) or replacement anaesthesiologist (E005C) gets E401 only if the case began after hours (GP87, GP95).

What is E401C often billed with?

The assistant's or anaesthetist's claim for the procedure, for example caesarean section P018B or P018C (K6, GP87, GP94). C999B or C999C when the physician travels in for the night case (GP88, GP94). On the assistant's claim, E676B (6 units) for a morbidly obese patient (BMI over 40, recorded in the chart) when the procedure is on the E676 list, which includes P018 (SP6 to SP7).

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Billing code

E401C — Nights (00:00 - 07:00) - Add 75%

Q: What is OHIP billing code E401C?

After-hours premium of 75% on the surgical assistant's (E401B) or anaesthetist's (E401C) total fee when the case starts at night, 00:00 to 07:00.

Night anaesthesia premium

Adds 75% to the assistant's (E401B) or anaesthetist's (E401C) total fee when the case starts between 00:00 and 07:00.

Watch for: A case that starts before midnight takes E400, even if it runs past 00:00; surgeons use E410.

Provider	Specialist	Assistant	Anaesthetist	Non-anaesthetist
$0.00	$0.00	$9.68	$11.97	$11.97

Code: E401C
Description: Nights (00:00 - 07:00) - Add 75%
FHO+ basket: Not in the FHO+ base rate basket (Schedule 2 or 2B).
Effective date: Apr 1, 2026
Termination date: No end date

Explanation

Updated October 26, 2026

After-hours premium of 75% on the surgical assistant's (E401B) or anaesthetist's (E401C) total fee when the case starts at night, 00:00 to 07:00.

What it covers

E401B increases the total surgical assistant's fee by 75%, and E401C increases the total anaesthetic fee by 75%, when the case commences at night, 00:00 to 07:00 (GP87, GP94).

The total fee is the basic units plus time units multiplied by the unit fee (GP85, GP92). Evening and weekend or holiday daytime cases take E400 (+50%) instead (GP87, GP94).

Billing rules

Based on when the case commences: a case that starts before midnight takes E400, even if it runs past 00:00 (GP87, GP94).
For the assistant (B suffix) and anaesthetist (C suffix) only. The surgeon's night premium on the procedural fee is E410, which has its own criteria (GP87, GP94, GP103 to GP104).
A replacement assistant (E005B) or replacement anaesthesiologist (E005C) gets E401 only if the case began after hours (GP87, GP95).
Surgical assistant standby (E101B) is payable with after-hours premiums (GP91).
The night special visit premiums C999B (assistant) and C999C (anaesthesia), with no maximum per period, are payable in addition when the physician travels in (GP88, GP89, GP94).

Often billed with

The assistant's or anaesthetist's claim for the procedure, for example caesarean section P018B or P018C (K6, GP87, GP94).
C999B or C999C when the physician travels in for the night case (GP88, GP94).
On the assistant's claim, E676B (6 units) for a morbidly obese patient (BMI over 40, recorded in the chart) when the procedure is on the E676 list, which includes P018 (SP6 to SP7).

Related codes: E400, C999, E005, E101, E410, E676, P018

Source: Schedule of Benefits (July 1, 2026), General Preamble, Surgical Assistants' Services, After Hours Premiums, page GP87, and Anaesthesiologists' Services, After Hours Premiums, page GP94

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