https://www.canada.ca/en/revenue-agency/programs/about-canada-revenue-agency-cra/corporate-reports-information/underground-economy-strategy-2022.html
The CRA is continuously monitoring UE activities to determine its scope and scale. To better understand the nature of the UE, the Agency has, since 2009, collaborated with Statistics Canada to quantify the extent of the UE in Canada. The findings, coupled with information from other sources, help the CRA in refining the focus and actions to combat the UE.
The estimated gross domestic product (GDP) at market prices for UE activity in Canada reached $68.5 billion, or 2.7% of total GDP, in 2021. From 2019 to 2021, the UE as a proportion of GDP has remained fairly stable between 2.7% and 2.8%. Both the overall and underground economies experienced a dip in 2020 at the onset of the COVID-19 pandemic, and UE activity subsequently stabilized to pre-pandemic levels in 2021.Footnote6
According to Statistics Canada, in 2021 four industries accounted for more than half of all UE activity:
residential construction (35.0%)
finance, insurance, real estate, rental, leasing, and holding companies (12.7%)
retail trade (10.5%)
accommodation and food services (7.3%)
These industries have been the main contributors to UE activity within Canada since Statistics Canada's study began in 1992.