The Red Knot breeds in the high Arctic, but migration routes and wintering grounds differ among and within the three recognized subspecies that occur in Canada. Calidris canutus islandica breeds in the High Arctic of northeastern Canada and Greenland, and migrates to Europe. C.c. roselaari breeds in northern Alaska and Wrangel Island (Russia), and winters along the Pacific coast of Mexico and California, with only a small number known to stop along the British Columbia coast during migration. C. C. rufa breeds in the central Canadian Arctic from Banks Island in the west to Baffin Island in the east, and is subdivided into three populations that winter in Tierra Del Fuego, northeastern South America, and the southeastern United States and Caribbean.

Approximately 40% of the global population of C. c. islandica breeds in Canada, corresponding to a moderate level of jurisdictional responsibility. The Canadian breeding population is estimated at approximately 1.16 million individuals based on recent analysis of data from the Arctic Program for Regional and International Shorebird Monitoring (PRISM). This is several times higher than the previous global estimate, but likely reflects improved methods rather than an increase in abundance. Although continental and global estimates have not yet been formally updated, this means that the global population is likely around 2.9 million individuals. It was designated as Special Concern by the Committee on the Status of Endangered Wildlife in Canada in 2007, but reassessed as Not at Risk in 2020 based on evidence of a fairly large and stable population. However, the population is not sufficiently monitored to estimate a long-term trend or define a population goal, and it is therefore considered data deficient.

C. c. roselaari breeds in Alaska, and while most of the 22,000 individuals pass through Canada on migration, only a small number are known to stop in Canada during migration, corresponding to at most a moderate level of jurisdictional responsibility. The global population appears to have undergone a large decline since 1970, based on migration monitoring by the Program for Regional and International Shorebird Monitoring. Although reliability is low, the population is clearly below its goal range. It was designated as Threatened by the Committee on the Status of Endangered Wildlife in Canada in 2007, and reassessed at the same level in 2020.

The entire global population of C. c. rufa breeds in Canada, corresponding to a very high level of jurisdictional responsibility. There is high confidence in the overall population having experienced a very large decrease since 1970, based on drastic declines shown through migration monitoring by the Program for Regional and International Shorebird Monitoring and various winter site surveys. The subspecies was designated as Endangered by the Committee on the Status of Endangered Wildlife in Canada in 2007. When reassessed in 2020, it was subdivided into three populations wintering in different regions. Those wintering in Tierra del Fuego (approximately 7,500 individuals) and in the southeastern United States and Caribbean (approximately 9,300 individuals) retained an Endangered status, while the population wintering in northeastern South America (approximately 20,000 individuals) was down-listed to Special Concern. All three rufa populations are below their goal ranges.