I try and include this reminder in my newsletter and/or blog post each year…so this is a repeat…
As employers prepare T4’s, they can make like a bit easier for staff. By reporting the employees contributions to the health and dental premium in Box 85, you are helping staff make sure they get the medical Expense Tax Credit (METC) where available. This avoids employees being audited for proof of contributions (and you having to write out letters for them).
You can find more about the history of box 85 and it’s intent here… https://www.canadianmoneysaver.ca/blog/box-85-is-my-box
The CRA info is below, or ask your accountant. https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/payroll/benefits-allowances/private-health-services-plan-premiums.html