The COVID-19 pandemic adversely affected the delivery of essential health services globally. In this study, we aimed to assess the impact of the pandemic on HIV testing and linkage services at three public health facilities in Freetown, Sierra Leone. We conducted a retrospective study to assess the impact of COVID-19 on HIV testing and linkage to treatment services (HTS) at Connaught Hospital (CH-tertiary), Lumley Government Hospital (LGH-secondary) and George Brooke Community Health Center (GBC-primary) in Freetown. Statistical analyses were conducted in Stata (16.1, StataCorp LLC, College Station, TX). Intra-pandemic HTS (2020) and HTS during recovery (2021) were compared with pre-pandemic HTS (2019). Of the 8538 people tested for HIV in the three facilities, 4929 (57.5%) visited CH. Only 2249 people were tested for HIV in 2020 compared to 3825 in 2019 (difference: - 41.2%, P < 0.001). Fewer people were also tested in 2021 (difference: - 35.6% P < 0.001). The largest reductions in testing in 2020 occurred in women (- 47.7%), children under 15 (- 95.2%), married people (- 42.6%), and CH (- 46.2%). Overall, 1369 (16.0%) people were positive for HIV; CH (878, 17.9%), LGH (469, 15.6%) and GBC (22, 3.5%). The likelihood of a positive HIV test was 26% lower in 2020 than 2019 (PR 0.74; 95% CI 0.64-0.85; P < 0.001), but 16% higher in 2021 than 2019 (PR 1.16; 95% CI 1.03-1.30; P < 0.05). Of the 1369 HIV diagnosis, 526 (38.4%) were linked to care. We found significant disruptions in HIV testing and linkage services at different levels of service delivery during the COVID-19 pandemic, underscoring the need to strengthen essential health services during public health emergencies.