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Billing code

C601A — Complex Medical Specific Re-assessment

Cardiology complex in-patient re-assessment

Bill when a cardiologist re-assesses a hospital in-patient because the condition is complex, obscure or serious.

Watch for: Send a written report to the patient's primary care physician, or it pays as a lesser assessment.

Code

C601A

Description

Complex Medical Specific Re-assessment

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

Complex medical specific re-assessment by a cardiologist for a hospital in-patient whose condition is complex, obscure or serious.

What it covers

C601 is a complex medical specific re-assessment by a cardiologist for a non-emergency hospital in-patient (A80).

It is a re-assessment because of the complexity, obscurity or seriousness of the patient's condition and includes all the requirements of a medical specific re-assessment (GP24).

Billing rules

• Send your findings, opinions or recommendations in writing to the patient's primary care physician, or it pays as a lesser assessment (GP24).
• Limited to 4 per patient per physician per 12 months (GP24).
• Medical specific assessments and complex medical specific re-assessments together are limited to 4 per patient per physician per 12 months (GP23, GP24).
• The congestive heart failure premium (E088) is not payable for in-patients (A79).
• Virtual care: video only, not phone (Appendix J, AJ2). For an in-patient, you must not be the MRP, the hospital must lack a local physician with the expertise (documented by the referrer), and the referrer must have seen the patient in person within 30 days (A69).
• For emergency calls and other special visits to in-patients, bill the A-prefix General Listings with special visit premiums instead (A80, GP65–GP78).

Often billed with

• C101 ICU/CCU premium for each patient seen on a visit to the ICU or CCU, unless a critical care, ventilatory or comprehensive care team fee is claimed (GP103).

Common rejections

• AT2: OHIP's message is 'Must Include Video Modality': in-patient (C-prefix) virtual services are video only, so a phone claim (K301A) is refused (AJ2).

Related codes: A601, C603, C604, C600, C602

Source: Schedule of Benefits (July 1, 2026), Consultations and Visits, Cardiology (60), page A80; rules GP23–GP24.

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