Abstract Results of an economic study associated with the implementation and maintenance of HACCP in a pasteurized milk plant are presented. The GMP/SSOP pre-requisites were evaluated in the plant. Two HACCP plans were proposed: a first plan was developed under the actual operating conditions, without previous compliance of GMP/SSOP pre-requisites, and a second plan was developed considering compliance of GMP/SSOP. The cost estimation for implementation and maintenance of HACCP, with or without previous adoption of the pre-requisite programs, was performed and a comparative analysis of the estimated values was carried out. The results suggest that a previous compliance of GMP/SSOP pre-requisites is essential for developing an effective HACCP plan with a small number of critical control points, leading to lower costs and investments for implementation and maintenance of HACCP.