Tidal computations are reported for the Gulf of Maine with emphasis on its seaward banks. Georges Bank, Browns Bank, Nantucket Shoals, and the nearshore region off Cape Sable. The model is 3D and nonlinear, with quadratic vertical viscosity; stratification is ignored. The objective is to establish a theoretical baseline for tidal and residual currents on detailed topography against which seasonal changes may be examined. Two triangular meshes are used. The base case corresponds to earlier studies with roughly 6-km resolution on the banks. A more refined and extended mesh provides resolution at 2–3 km in critical areas and has boundaries farther removed from the banks. Both meshes provide very good fits with observed M2 elevations. Comparison of computed and observed M2 current profiles at 76 sites reveals general agreement that improves with resolution. For the refined mesh and the 48 sites with records exceeding 60 days, average deviations for M2 ellipse parameters are (6.1, 4.7) cm s−1 for the ... Abstract Tidal computations are reported for the Gulf of Maine with emphasis on its seaward banks. Georges Bank, Browns Bank, Nantucket Shoals, and the nearshore region off Cape Sable. The model is 3D and nonlinear, with quadratic vertical viscosity; stratification is ignored. The objective is to establish a theoretical baseline for tidal and residual currents on detailed topography against which seasonal changes may be examined. Two triangular meshes are used. The base case corresponds to earlier studies with roughly 6-km resolution on the banks. A more refined and extended mesh provides resolution at 2–3 km in critical areas and has boundaries farther removed from the banks. Both meshes provide very good fits with observed M2 elevations. Comparison of computed and observed M2 current profiles at 76 sites reveals general agreement that improves with resolution. For the refined mesh and the 48 sites with records exceeding 60 days, average deviations for M2 ellipse parameters are (6.1, 4.7) cm s−1 for the ...