This sampling frame is a set of grid-based, finite-area frames spanning the offshore areas surrounding Mexico, and is intended for use with the North American Bat Monitoring Program (NABat). A Generalized Random-Tessellation Stratified (GRTS) Survey Design draw was added to the sample units from the raw sampling grids (https://doi.org/10.5066/P9XBOCVV). The GRTS survey design algorithm assigns a spatially balanced and randomized ordering (GRTS order) to each cell within its respective framework. Grid cells are prioritized numerically; the lower the number, the higher the sampling priority. Cells can then be selected for monitoring following the GRTS order, ensuring both randomization and spatial balance. Monitoring within this standardized framework allows statistical inference to non-surveyed locations and ensures the validity of analyses at regional and range-wide scales. NABat is a continental collaboration including state and provincial, federal, and local agencies intended to standardize the collection and storage of bat data. Grid boundaries are based on World Exclusive Economic Zone oceanic political boundaries and extend into the shoreline 30 kilometers.