Abstract Background The COVID-19 pandemic has posed unprecedented challenges to routine immunization programs globally. There is a growing body of evidence highlighting the impact of the pandemic on other routinely administered public health services. Understanding vaccination trends for routinely administered vaccinations during the pandemic is crucial for addressing potential gaps in protection and devising targeted strategies to enhance routine immunization programs. Objectives This study investigates the impact of the pandemic on routine immunization coverage in Canada, focusing on DTaP (Diphtheria, Tetanus, and Pertussis) with at least 4 doses and MMR (Measles, Mumps, and Rubella) with at least 1 dose, among children at age 2. Design/Methods Data were collected from the Routine Childhood Vaccination Coverage Surveillance system (RCVCSS) a novel national surveillance based on standardized detailed reports prepared by participating provinces and territories using data from their immunization registries. This analysis covers the years 2019 to 2022, capturing pre-pandemic, pandemic, and post-pandemic phases with data from 4 reporting provinces and territories (Alberta, Saskatchewan, New Brunswick and Yukon). The primary objective was to assess any changes in vaccination coverage at age 2 for routinely administered immunizations from 2019 to 2022, i.e., before, during and after the COVID-19 pandemic. Results Analysis reveals a decline in routine immunization coverage from 2019 to 2022. DTaP vaccination coverage at age 2 decreased from 82.0% in 2019 to 71.8% in 2022. Likewise, MMR vaccination coverage at two years showed a decline from 90.8% in 2019 to 81.7% in 2022. Similar downward trends in coverage were observed for other sets of antigens vaccinated against at age 2 including Varicella, Rotavirus, Polio, Pneumococcal and Hepatitis B. No major differences were observed when looking at vaccination coverage over time by sex. There were regional variations, with certain jurisdictions experiencing more pronounced declines than others and an increase in coverage in 2022 the post pandemic year. Conclusion There was a sustained decline in DTaP and MMR vaccination coverage at age 2 from 2019 to 2022. Further research is imperative to ascertain whether there has been a catch-up in vaccination coverage and to identify the root causes of the observed declines, so these can be addressed, and targeted interventions can be undertaken to allow coverage level to recover to their pre-pandemic levels.