< Billing codes

Billing code

G603A — Neonatal Low Birth Weight Intensive Care - Payable In Lieu Of G600 Or G603 For Newborn Less Than 750 Grams In Weight Or 26 Weeks Gestational Age

NICU Level A, sole newborn

Bill G603 instead of G600 or G604 for Level A neonatal intensive care when the infant is your sole newborn.

Watch for: Maximum 25 per physician per fiscal year (April to March); only one of G600, G603 or G604 applies.

Code

G603A

Description

Neonatal Low Birth Weight Intensive Care - Payable In Lieu Of G600 Or G603 For Newborn Less Than 750 Grams In Weight Or 26 Weeks Gestational Age

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

Level A neonatal intensive care when the infant is the physician's sole newborn, in place of G600 or G604. Maximum 25 per physician per fiscal year.

What it covers

Neonatal intensive care is a team fee for being in constant or periodic attendance over a one-day period to provide all aspects of care to Intensive Care Area patients. It includes the initial consultation or assessment, later assessments, ongoing monitoring, and procedures such as arterial, venous, C.V.P. or urinary catheters, IV lines, blood gas interpretation, nasogastric and endotracheal intubation, tracheal toilet and ventilation (J33).

G603 sits under Level A: full life support including monitoring, ventilatory support and parenteral alimentation (J33). It is payable in lieu of G600 or G604 if the infant is the sole newborn, to a maximum of 25 services per physician per fiscal year (J33).

Billing rules

• Bill instead of G600 or G604 when the infant is the sole newborn; only one of G600, G603 and G604 applies (J33).
• Maximum 25 services per physician per fiscal year (April 1 to March 31) (J33, GP2).
• These are team fees for neonatologists, paediatricians and anaesthesiologists giving complete care; the physician-in-charge is the physician(s) providing the care each day (J33).
• While billing neonatal intensive care, no other critical care codes are paid to the same physician(s) (J30).
• Life-threatening or other critical care (G521–G523, G395, G391) is not paid to the same physician on the same day as this per diem (J27, J28).
• C101 ICU visit premium and special visit premiums are not payable with NICU team fees (GP103, GP65).
• Add G556 when the initial NICU admission visit is at night (00:00–07:00); once per patient per admission (J35).

Often billed with

• G556 night-time ICU/NICU admission assessment premium (J35).
• Separately billable interventions done that day (J33).

Common rejections

• AM1: OHIP describes AM1 as 'Service Limit Exceeded': more than 25 G603 services by you in the fiscal year (J33).

Related codes: G600, G601, G604, G610, G620, G556

Source: Schedule of Benefits (July 1, 2026), Diagnostic and Therapeutic Procedures, Critical Care (Neonatal Intensive Care, Level A), page J33.

APEX checks every paid claim against the Schedule of Benefits and flags codes billed below what the visit qualified for. See how APEX works · Pricing