A study was conducted to evaluate conventional steam‐distillation techniques for N‐isotope analysis of inorganic forms of N in soil extracts. Extracts obtained with 2 M KCl from 10 diverse soils were treated with: (i) (15NH4)2SO4and KNO3, (ii) (NH4)2SO4and K15NO3, or (iii) KNO3and Na15NO2. Steam distillations were performed sequentially to determine NH4+‐N and NO3‐‐N, and were also carried out to determine (NO3‐+ NO2‐)‐N or (NH4++ NO3‐+ NO2‐)‐N; a pretreatment with sulfamic acid was used to determine NO3‐‐N in the presence of NO2‐‐N. Recovery of added N ranged from 95 to 102%. Significant isotopic contamination was observed in sequential distillation of unlabeled NO3‐‐N following labeled NH4+‐N; otherwise, analyses for15N were usually within 1% of the values calculated by isotope‐dilution equations.