Lowman is a small unincorporated rural census-designated place in the western United States, located in Boise County, Idaho. It is nestled along the north bank of the South Fork of the Payette River in the central part of the state, at an elevation of 3,800 feet (1,160 m) above sea level. As of the 2010 census, its population was 42.
Eighty miles (130 km) from Boise on State Highway 21, the "Ponderosa Pine Scenic Byway," Lowman is at the junction with the "Banks-Lowman Highway"; now designated Highway 2512A. It is the "Wildlife Canyon Scenic Byway," it vertically descends 1,000 feet (300 m) with the whitewater of the South Fork to its confluence with the North Fork at Banks, the junction with State Highway 55, the "Payette River Scenic Byway."
The "Highway to Heaven" trail, stretching more than 150 miles (240 km) from Idaho's capital of Boise, is the only mountain passage in the West that begins from a major city. The trail winds from 8th Street in Boise and climbs the Boise River, past the Lucky Peak Dam. Sagebrush gives way to gentle pine slopes leading to historic Idaho City, then over Mores Creek Summit at 6,117 ft (1,864 m) and switches back down to Lowman. The route then climbs with the South Fork of the Payette River up and over Banner Summit at 7,056 ft (2,151 m) to Stanley, where it meets State Highway 75 and the Sawtooths.
The community was named for a homesteader, Nathaniel Winfield Lowman, from Polk County, Iowa, who settled there in 1907; when he founded a post office four years later, it was named for him.
Lowman is in a geothermally active region. Natural hot springs surface in the middle of the community as well as in many other places in the surrounding mountains.
A devastating wildfire ravaged the area around Lowman 28 years ago in 1989; it destroyed 45,000 acres (180 km2) and 26 structures, but without injuries or fatalities.
Lowman has an area of 2.078 square miles (5.38 km2); 2.039 square miles (5.28 km2) is land, and 0.039 square miles (0.10 km2) is water.