The United Kingdom Overseas Territory of Montserrat supports modest but regionally important nesting populations of green and hawksbill turtles. However, knowledge of the spatial ecology and regional connectivity of these populations is limited. Here, we provide the first detailed description of the spatial distribution, migratory connectivity, and habitat use of 9 adult female green turtles Chelonia mydas and 1 adult female hawksbill turtle Eretmochelys imbricata tagged with satellite transmitters at 4 nesting beaches in Montserrat. Two critical aggregation areas for inter-nesting green turtles were identified along the western coast of Montserrat which could act as focal points for spatial protection. Nine individuals, including the hawksbill turtle, performed transboundary post-nesting migrations, covering distances from 45 to 1013 km, and crossing 10 different national jurisdictions. Green turtles migrated to foraging grounds in Antigua and Barbuda (n = 4), United States Virgin Islands (n = 2), Puerto Rico (n = 1), and Dominican Republic (n = 1), whereas the hawksbill turtle migrated to a foraging ground in Guadeloupe. One green turtle remained resident in Montserrat. Within foraging grounds, green turtles primarily occupied sand, seagrass, and hardbottom algal habitats located in shallow (<25 m) coastal waters. On average, turtles spent 22 and 24% of their time within Marine Protected Areas during migration and foraging periods, respectively. Our results provide novel insights into the ecology of individuals nesting at a previously understudied rookery that can be used to inform local and regional management.