[2] The highway travels west on Grandview Road, crossing over a railroad carrying the BNSF Railway's Bellingham Subdivision,[3][4] and passes through a rural area while following Fingalson Creek.

[5][6] The highway turns north onto Blaine Road at a roundabout near the complex's main entrance,[7] located east of Birch Bay State Park.

The highway crosses over the BNSF Bellingham Subdivision and turns northwest onto Peace Portal Drive, traveling parallel to I-5 and the railroad through Blaine.

[11] SR 548 reaches its terminus at a dogbone interchange with I-5, signed as exit 276, near the city's marina, approximately 1⁄2 mile (0.8 km) from the Peace Arch crossing of the Canadian border.

[13] SR 548 between Birch Bay and Blaine follows the route of a wagon road built in the 1900s parallel to a Great Northern rail line.