Abstract The accuracy of the Pre‐sidedress Soil Nitrate Test (PSNT) for predicting the need for sidedressing and for its ability to provide satisfactory nitrogen (N) rate recommendations for field corn grown on a diversity of soils and production systems was evaluated. Thirty‐five N‐response experiments were conducted over a six year period in New Jersey. Soil nitrate (NO3) concentrations were determined in the surface 30 cm of soil when corn plants were 30 to 45 cm tall. Soil nitrate‐nitrogen (NO3‐N) concentrations reflected differences in N availability due to manure application. The relationship between soil NO3‐N concentration and relative grain yield was examined using Cate‐Nelson analysis to define the PSNT critical level. Soil NO3‐N concentrations >22 mg/kg were associated with relative yields of 92% or higher. The success rate for the PSNT critical level was 81 % for making the correct predication as to whether sidedress N was needed. The PSNT is useful to determine the need for sidedress N, but P...