Nichols Run is a 3.73 mi (6.00 km) long first-order tributary to Tunungwant Creek.

[2] Nichols Run rises about 1 mile (1.6 km) west of Harrisburg, New York in Cattaraugus County and then flows northwest to meet Tunungwant Creek in Limestone, New York.

Nichols Run drains 4.10 square miles (10.6 km2) of area, receives about 44.6 in/year (113 cm/year) of precipitation, and is about 85.32% forested.