Highway 8 is a provincial highway in the Canadian province of Saskatchewan. It runs from North Dakota Highway 28 at the US border near Elmore until it transitions into Highway 982 just outside the Porcupine Provincial Forest. Highway 8 is about 410 kilometres (250 mi) long.

Highway 18 is a highway in the Canadian province of Saskatchewan. It runs from Highway 13 near Robsart, approximately 65 km (40 mi) east of the Alberta border, to the Manitoba border near Gainsborough, where it becomes Highway 3. It passes through three major communities, all in the eastern quarter of Saskatchewan – Estevan, Oxbow, and Carnduff; it also passes north of the west and east blocks of Grasslands National Park. Highway 18 is about 712 km (442 mi) long, which is the longest east-west highway and second longest highway in Saskatchewan.