Continuing northward as the county line approaches, NY 90 parallels it on a northeastward trek through Montezuma. Turning northward, the route comes within feet of the New York State Thruway (I-90) and bends eastward as it crosses on a parallel for several blocks. Reaching a junction with Fuller Road (CR 142), where NY 90 turns northward and crosses over the Thruway. North of the Thruway, NY 90 crosses through the hamlet of Montezuma, and reaches a junction with NY 31. This junction marks as the northern terminus of NY 90, which continues north of NY 31 toward Fox Ridge.