After crossing the railroad, the highway forms the eastern boundary of Ione Municipal Airport and later passes Sullivan Lake Road.

The railroad crosses the road and later bridges the Pend Oreille River, as the highway turns northwest and reverts northeast.

After turning south and back north, the highway starts to curve multiple times until intersecting Sullivan Lake Road and being directed northeast.

[3] SR 31's northern end at the Canada–US border is the easternmost crossing in Washington and is located east of Crawford State Park.

[8][9] SR 31's previous route ran a total of 73.31 miles (117.98 km) from Newport northwest to Tiger and north to the Canada–US border at BC 6.

[10] The route started in Newport at the intersection of W. Walnut Street (SR 31 northbound and US 2 eastbound) and N. Union Avenue (US 2 westbound).

Next, the highway went northwest and left Newport to parallel the Pend Oreille River for the rest of its route.

[11] The road would also join the Pend Oreille Valley Railroad north to the current southern terminus.

[4] SR 31 turned west and passed Lake Newport State Park, located on the shores of the river,[12] before curving northwest and entering the community of Dilkena.