In this paper a procedure based on the Finite Element Method and Linear Elastic Fracture Mechanics to obtain a mathematical model of crack propagation in transverse fillet welded joints is presented. We used ASTM-A36 steel plates and E6013 electrodes for the joints, using shielded metal arc welding (SMAW) as the welding process. The model uses a surface crack located in the weld toe. Differences of up to 41% in crack growth rates were found between cracks located 90% out of the bead mid plane with respect to the central crack. The straight and convex bead profiles were employed and according to the results there were no significant differences in fatigue life for both kinds of bead profiles. The results of the models were compared with conventional weld calculations and validated with experimental tests. The theoretical fatigue life values were within the statistical confidence interval for p=95%.Universidad de Ibagu?