Background: After SARS-CoV-2 reached the Netherlands in February 2020, rapid interventions were taken to mitigate viral spread and optimise care for COVID-19 patients. Lockdowns and downscaling of regular healthcare practices were necessary to scale up COVID-19-related care. The effect of these interventions on HIV care are uncertain. We assessed the impact of the nationwide lockdown in March and May during the first COVID-19 wave on HIV diagnosis and linkage to care. Methods: An observational study was conducted at the Erasmus MC, a regional reference tertiary hospital in the Netherlands. All patients ≥ 18 years presenting with HIV indicator conditions (ICs) were identified in electronic patient records, using an automated identification system for ICD-10 and health insurance codes. Primary outcomes measured were the number of HIV tests performed, number of HIV ICs and corresponding HIV testing rates, and new HIV diagnoses before, during and after lockdown. Results: From January to April, all newly registered diagnoses decreased by 35%, and in patients referred for HIV ICs by 69% (figure 1). The proportion of patients presenting with HIV ICs that were adequately tested for HIV remained relatively stable, especially where HIV testing is standardised, even during lockdown in March, April and May when a cumulative 328 proven or suspected COVID-19 patients were admitted. The absolute number of HIV tests performed during the first half year of 2020 was 13% lower than the same period in 2019, and new HIV patient referrals dropped 67%. The number of HIV IC, HIV testing rates and HIV referrals showed recovery after the lockdown. Conclusion: The first two pillars of the HIV care continuum were affected by the lockdown during the COVID-19 pandemic. Standardisation of HIV testing could prevent diagnostic delays to a certain extent. With an eye on subsequent COVID-19 waves, these data indicate that maintaining focus on adequate identification and testing of patients with undiagnosed HIV is essential to prevent unwanted declines affecting the 95-95-95 goals.