For the first time, in 2020 CMHC added questions to its annual October Rental Market Survey to explore the level of rent arrears, a concern heightened by the COVID pandemic. This new data source reveals a wide range of arrears rates with Windsor recording the highest arrears rate of 22% compared to a national average of 6.6%. This represents the percentage of units in arrears across the full 2.050 million universe of purpose built rental units. This brief explores the new data and assesses the severity of arrears, which have been significantly influenced by the COVID19 pandemic.