A simple block digester for total soil N measurement was assembled from a small low‐temperature aluminum block and a hot plate. The samples are digested in 16 mm diameter heat resistant glass tubes using H2SO4and a digestion mixture composed of CuSO4and K2SO4. The ammonium content in the digest is determined colorimetrically. The proposed method employs equipment found in most small laboratories and therefore provides the capability of precise in‐house N‐determination at minimal cost.