Following its intersection with Eckstein Road (TR 166), SR 181 crosses over the US 30 freeway, and arrives at its endpoint at SR 309, a T-intersection located just  west of the Ontario city limit.
SR 181 intersects with Eckstein Road (TR 166) and then crosses over the US 30 freeway. It eventually reaches its terminus at SR 309, a four-way stop located near the edge of the Ontario city limits.