K-143 is a 4.658-mile-long (7.496 km) north–south state highway in Saline County, Kansas. The route runs through lands mostly used for agriculture from an interchange at Interstate 70 (I-70) and U.S. Route 40 (US-40) in northern Salina, Kansas generally northward to a junction with US-81 north of Salina. The southern part of the route is a four-lane divided highway while the rest is a two-lane highway. It has an annual average daily traffic (AADT) between 1,580 and 4,133 vehicles. The route is paved with three different pavement types, and is not a part of the National Highway System. It was first designated as US-81 Alternate in the early 1970s with the designation being changed to K-143 in the early 1980s.