Purpose: Globally, 25 million children were either unvaccinated or under-vaccinated in year 2021. Among them, India had the highest number of children unvaccinated. Studies have shown impact of coronavirus disease 2019 (COVID-19) pandemic on routine health-care services. Present study aimed to estimate the impact of COVID-19 on utilization of routine immunization services during years 2020 and 2021 in tertiary-care facility. Materials and Methods: Record based descriptive analytic study was conducted at pediatric tertiary-care hospital, Jaipur. Data of children vaccinated as per the National Immunization Schedule for the period January 2019 to December 2021 were retrieved from the immunization records. Doses administered were assessed as a proxy measure of vaccine coverage. The vaccination trends of 2020 and 2021 were compared assuming base year 2019. Unpaired t-test of significance and Pearson correlation was used for correlation analysis. Results: There was significant drop in the vaccine counts after emergence of COVID-19 pandemic. In year 2020 and 2021, mean monthly vaccine count was 2,190±715.1 and 2,305±393.2, respectively, in which maximum drop was in April 2020 (-79.12%) and May 2021 (-57.16%) when it was compared with matched month of base year. There was negative correlation between percent change in vaccine count and COVID-19 cases in 2020 (r=-0.057, p=0.861) and 2021 (r=-0.827, p=0.001) as compared to year 2019. Conclusion Study concludes that there was a significant gap in utilization of routine immunization services during the COVID-19 pandemic. This necessitates planning and management of routine immunization services in-case of future pandemics to avoid resurgence of vaccine-preventable diseases in the Rajasthan.