Since its first detection in 1996, infectious salmon anemia has been a viral disease of significant concern for farmed salmon in the Atlantic provinces of Canada. Several epidemiological aspects of ISA outbreaks in Atlantic Canada remain incompletely understood. The objectives of this study were to describe the spatio -temporal patterns of infectious salmon anemia virus (ISAv ) outbreaks during marine phase of production of farmed Atlantic salmon in Newfoundland and Labrador (NL) and explore risk factors associated with the timing of outbreak detection and depopulation at affected sites. ISAv surveillance data (2012- 2020) were provided by the Aquatic Animal Health Surveillance Program led by NL Department of Fisheries, Forestry, and Agriculture. Final analyses included fish and site-level data consisting of 94 sampling events and 20 Atlantic salmon production sites. ISAv detection was based on RT-PCR with genotyping for moribund and harvested fish samples. Linear regression models were used to investigate factors influencing time-to-detection (days from stocking to first ISAv detection) and time-to-depopulation (days from the first detection to site depopulation). During the study period, a total of 28 unique outbreaks were reported. Site-level annual incidence risk of ISAv detection was 3-33% and fish-level annual detection in sampled fish was 2-45%. European (EU) ISAv genotype detections were more common compared to North American (NA) genotypes. The variables, ISAv genotype, neighboring farm outbreaks, and year of the outbreak were not associated with the time to first ISAV detection. Outbreaks with NA genotypes had significantly shorter (p= 0.02) time to depopulation compared to EU genotypes. Time to depopulation was also significantly shorter (p=0.0004) if ISAV was first detected at a site from 20 16-2018, compared to 2012-2015. The annual risk of ISAv detection in marine salmon farming sites in NL varied over years at both fish and site levels. Time to depopulation was inversely associated with ISAV’s North American genotype and the year of the first detection.