Background: Understanding the impact of pandemic measures on elderly mobility is crucial for shaping public health responses. This retrospective study assesses the changes in mobility of 216 elderly individuals (average age 84 years) in the Czech Republic before and during COVID-19 restrictions, using two years of GPS tracking data. Methods: We conducted statistical analyses across various physical, demographic, and social factors. Data were analyzed for mobility patterns, SOS alarm usage, and relationships between mobility and factors such as age group, body mass index, sex, city size, and housing type. Results: During the study, 4409 SOS alarms were triggered, with only 16.6% requiring action. Alarms triggered outside the home decreased from 34% pre-COVID-19 to 29% during COVID-19, reflecting reduced outdoor activity. Mobility decreased by 43.9% overall during the pandemic. The largest year-on-year decline in mobility was in May, reaching 57.6%. However, 10% of the participants exhibited increased mobility. Factors such as age group, body mass index, sex, city size, and type of housing were analyzed, and we found that city size and housing type did not significantly influence mobility levels. Conclusions: These findings highlight the substantial decline in elderly mobility during the COVID-19 pandemic and emphasize the need for tailored interventions, such as outdoor mobility programs and telemedicine, to support elderly populations during public health crises.