Statistics Canada has acknowledged a significant undercount of non-permanent residents in the 2021 census, estimating that it likely missed several hundred thousand individuals. Non-permanent residents include students, temporary foreign workers, and asylum seekers. A recent report suggests that approximately 38 percent of this population was not accounted for in the census, which officially recorded 924,000 non-permanent residents in Canada.

The report does not provide a specific number of individuals missed but warns that the missed rate may include those who were miscounted or had already left the country. Based on the 38 percent undercount, it is estimated that around 576,000 individuals were not reached by census-takers. This figure exceeds the population of Halifax. However, it is significantly lower than previous estimates by external analysts, who suggested the undercount could be as high as one million.

In 2023, economist Benjamin Tal from CIBC estimated that the census undercounted non-permanent residents by about one million. He indicated that the official count was short by approximately 250,000, with an additional 750,000 overstaying their visas and not included in Statistics Canada’s figures. Tal stated, "between the clear understating of (non-permanent resident) counts in the census, and the exclusion of overstayers in the quarterly demographics statistics, the number of (non-permanent residents) that are missing from official statistics used by planners is approaching one million."

Statistics Canada recognized the undercount shortly after the 2021 census was completed. The census recorded a total population of 36,991,981, while the official estimate at that time was 38,192,700, indicating a discrepancy of about 1.2 million. The agency explained that some individuals are not counted because their households did not receive a census questionnaire or because they were not included in the responses provided.

Non-permanent residents have historically been among the most undercounted demographics in Canadian censuses. In the 2016 census, Statistics Canada estimated that it missed about 45 percent of non-permanent residents, which translated to approximately 415,000 individuals. In 2011, the undercoverage rate was 43 percent, missing around 269,000 people.

The undercounts from the 2021 census are particularly notable as they occurred during a period of unprecedented growth in the non-permanent resident population. Current figures from Statistics Canada indicate that the non-citizen population has risen to 3,024,216, more than double the number recorded in the 2021 census.

In recent testimony before the House of Commons, officials from agencies overseeing non-permanent residents confirmed that many individuals remain unaccounted for. A representative from Immigration, Refugees and Citizenship Canada reported that 47,175 foreign students were “non-compliant,” meaning they were not adhering to the terms of their student visas and their whereabouts were unknown. Additionally, a representative from the Canada Border Services Agency stated that they had lost track of 32,000 foreign nationals under deportation orders.