Saint Pierre and Miquelon is a French archipelago in North America, with a population of 5,974 in 2019. Starting in March 2020, the territory’s health authorities adopted a zero-COVID strategy to protect the population and healthcare facilities. This article describes the epidemiological dynamics of COVID-19 in Saint-Pierre-et-Miquelon in light of the evolution of the strategies implemented from March 2020 to May 2022. All public health measures were obtained from the prefecture, and epidemiological surveillance and vaccination data were sourced from networks established by the Territorial Health Administration (ATS) and emergency department visit summaries (RPU). Following a strict 6-week lockdown, measures for isolating cases and contacts, along with a significant reduction in air traffic, were implemented. Vaccination was offered to the entire population in March 2021 and was rapidly accepted across all age groups. No community transmission was observed prior to November 2021; subsequently, three epidemic waves occurred in succession, reaching a peak incidence rate of 9,687 cases per 100,000 inhabitants. A single death linked to COVID-19 was recorded. The virus’s entry into the territory coincided with the emergence of new variants and the easing of public health measures. The zero-COVID strategy implemented in Saint-Pierre and Miquelon helped delay the virus’s entry into the territory, allowing time to prepare health infrastructure and enable as many people as possible to get vaccinated. This strategy contributed to the virus’s limited health impact, but at the cost of severe isolation of the territory and its populations for a year and a half.