C635 – Consultation
OHIP Surgical Procedures Code — Nuclear Medicine (63) · Schedule of Benefits
A consultation for a non-emergency hospital in-patient rendered following a written request from a referring physician, nurse practitioner, or dental surgeon. The consultant physician provides an expert opinion due to the complexity, seriousness, or obscurity of the case, or because a second opinion is requested. This service includes a general, specific, or medical specific assessment, a review of all relevant data, and the preparation of a written report to the referring practitioner. The 'C' prefix indicates the service is for an acute care hospital non-emergency in-patient, as defined in .
When to Use
- Use C635 when you are requested by a primary care provider or specialist to provide an expert opinion on a complex, non-emergency in-patient case that requires a formal written report.
- Use C635 for a second opinion on a patient's diagnosis or management plan when the referring practitioner specifically requests your expertise for an in-patient admission.
- Use C635 when the patient's condition is sufficiently complex to warrant a comprehensive assessment and a detailed written report back to the referring practitioner, distinguishing it from a standard subsequent visit (C636).
Common Pitfalls
- Billing C635 without a documented, written request from the referring practitioner, which leads to automatic rejection or reduction to a lower-value assessment fee upon audit.
- Failing to send a formal written report to the referring practitioner, as the absence of this report invalidates the consultation claim and triggers a payment adjustment.
- Billing C635 for a request initiated by a medical trainee, which is ineligible for the consultation fee and will be downgraded to a standard assessment.
Billing Tips
- Ensure the written request in the hospital chart explicitly names you as the consultant and the referring practitioner, as missing identifiers are a frequent cause of claim rejection.
- If you are managing a patient for the same diagnosis for which you have already been paid a consultation, subsequent visits must be billed as C636 rather than repeating C635.
Effective: June 1, 2025
Consultations and Visits
Nuclear Medicine (63)
Consultation
Consultations, Hospital and Institutional Consultations and Assessments
A copy of the written request for the consultation, signed by the referring physician, nurse practitioner or dental surgeon must be kept in the consulting physician's medical record. In a hospital where common medical records are maintained, the written request may be contained on the common medical record.
The request must identify the consultant by name, the referring practitioner by name and billing number, and the patient by name and health number.
The written request must set out the information relevant to the referral and specify the service(s) required.
The consultant is required to prepare a written report (including findings, opinions, and recommendations) to the referring practitioner.
Physician in hospital but not on duty in the Emergency Department when seeing patients in the Emergency or OPD - use General Listings.
For non-emergency hospital in-patient services, see General Preamble to . For emergency calls and other special visits to in-patients, use General Listings and Premiums when applicable - see General Preamble to .
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