Ontario is reporting 511 COVID-19 cases and no additional deaths from the virus on Sunday.
Health Minister Christine Elliott says 350 of the infected people are unvaccinated and 67 people are partially immunized.
The new case figures are based on 19,192 tests.
There are 116 patients hospitalized in Ontario with COVID-related critical illness, and 71 patients are on ventilators.
81 per cent of Ontarians aged 12 and older have received at least one dose of a COVID-19 vaccine and 73 per cent are fully vaccinated.
The province says it administered 50,343 vaccine doses since the last update, for a total of more than 20 million shots.