Introduction The coronavirus disease 2019 (COVID-19) pandemic has had immense impact on people and institutions, including the number of admissions to hospitals for surgery. Our aim in this study was to determine the impact of the pandemic on surgeries in a single institution located in Fukuoka, Japan, between 2019 and 2020. Methods We quantified the numbers of surgeries in both years according to three sites of injury (indoor, outdoor, and unknown), 14 disease categories, and 9 primary diseases using patients’ medical records. We also compared the hospital cost per day in each month from March to November in both 2019 and 2020 and compared the change in these costs between the two years. Results The number of admissions in 2020 was 1,187 cases vs 1,282 cases in 2019. The average patients’ age was higher in 2020 vs 2019 (69.7 ± 0.5 vs 67.5 ± 0.5 years, respectively; p = 0.004), with no gender differences (2020: 705 women and 482 men; 2019: 716 women and 566 men). We found no significant differences in the number of admissions by month between 2019 and 2020. The percentages of outdoor injuries were significantly lower in 2020 vs 2019 (29.8% vs 37.9%, respectively; p = 0.004), and we found significantly different rates when comparing 2020 and 2019 for degenerative disease (42.6% vs 37.4%; p = 0.007), trauma related to falls (34.4% vs 30.2%; p = 0.02), chronic disease (1.9% vs 3.7%; p = 0.005), and sports injuries (0.8% vs 3.7%; p < 0.0001). The rate of sports-related injury was significantly lower in 2020 (1.6%) than in 2019 (7.7%) (p < 0.0001). The daily hospital charge was $10,517.09 (US dollars) in 2020 vs $11,225.32 in 2019, and the charges in the months of April and June were significantly higher in 2020 vs 2019 (p = 0.003 and p = 0.001, for April and June, respectively). Both the number and rate of upper limb fractures were higher in 2020. Conclusions The COVID-19 pandemic is affecting some hospitals’ revenue. Although the charges per day were sufficient in our institution in 2020, compared with 2019, some hospital beds were unused during this phase of the pandemic. Hospitals may increase the revenue by mixing both short-term and long-term patients’ hospital stays effectively.