The previous record was 4,602 cases on Nov. 8. The country now has 282,296 cases in total.
Canada also added 83 more deaths, bringing its death toll to a total of 10,768.
Ontario reported 1,575 cases Thursday, the third day in a row the province has broken its own record for number of cases and the seventh straight day it has counted more than 1,000 cases.
The province now has a total of 89,784 cases.
Ontario also reported 18 more deaths, the largest increase since the beginning of October. Its death toll now stands at 3,293.
There are currently 11,271 active cases in the province, with 431 people in hospital — 98 of them in intensive care and 62 on a ventilator. Hospitalizations have steadily increased over the last few weeks.
Quebec reported slightly fewer cases than Ontario Thursday with 1,365 new cases, to bring its total to 119,894.
The province also reported 42 more deaths, nine of which occurred in the last 24 hours. There have now been 6,557 deaths in the province.
There are currently 583 Quebecers in hospital due to COVID-19, with 86 in intensive care.
Out west, British Columbia added 594 cases Thursday, a new record for the province.
B.C. now has more hospitalizations related to the coronavirus than it has before, with 155 people currently in hospital, 44 of which are in intensive care.
The province also recorded four new deaths to bring its total to 288.
In Alberta, 860 new cases were reported Thursday, along with 10 new deaths to bring its total to 393.
The province currently has 8,305 active cases and 225 people in hospital, with 51 of them in intensive care.
Saskatchewan added 111 new cases to bring its total to 4,437 and set a new record of hospitalizations for the fourth day in a row with 49 currently in hospital, 13 of which are in intensive care.
The province has had 29 deaths so far.
Manitoba reported nine new coronavirus-related deaths and matches a record set Wednesday. The province has 132 deaths so far.
Manitoba also added 474 new cases Thursday to bring its total to 9,782, with 227 people currently in hospital and 34 in ICU — both record numbers.
Out east in the Atlantic bubble, New Brunswick reported one new case related to travel outside the bubble, to add to its 13 active cases.
One New Brunswicker is currently in hospital with COVID-19 and in intensive care.
The province has seen six deaths from the virus.
Yukon also reported one new case to bring its total to 24.
Nova Scotia, PEI, Newfoundland and Labrador, and the rest of the territories reported no new cases or deaths.
There have been 52,629,906 confirmed cases of COVID-19 worldwide since the pandemic began, according to Johns Hopkins University, and 1,291,837 deaths.
— With files from Global staff