Accurate, rapid testing of soil nitrate-N concentrations would allow producers to adjust fertilizer rates and augment annual soil testing. This study tested the accuracy of three quick tests: test strips, a color disc and a portable colorimeter. A variety of Montana soils (n=89) were extracted with a 0.14 M MgSO₄ solution. Quick nitrate-N measurements were well correlated (P<0.001) with laboratory readings (mg kg-dry soil^-1) when the average moisture content was used. The r² values between laboratory and quick test readings were 0.79, 0.83 and 0.63 for the test strip, color disc and colorimeter, respectively. Soil water content affected the differences in nitrate-N readings between laboratory and quick test measurements (P<0.05), while no significant effects on readings were observed for either pH or clay content. Based on the lower correlation for the colorimeter, this method was excluded from the remainder of the analyses. Despite high correlation coefficients between laboratory and quick test readings, there was a 40% probability of over- or under-estimating total soil nitrate-N (upper 60 cm) by at least 16 kg N ha^-1. When the test strip and color disc methods were verified by five individuals, there was a moderate degree of variability in laboratory and quick test correlation coefficients (r² = 0.70-0.94). Regression coefficients between quick test and laboratory test data varied by up to a factor of 2.2 among individuals, apparently due to differences in color interpretation. Therefore, if one correction factor was used to calculate nitrate-N concentrations from a quick test as has been previously recommended, an error of approximately 100% could be introduced. Steps to increase accuracy when using these methods include: measuring soil water content, following a consistent methodology, and calibrating quick test readings with laboratory results.