This paper provides a numerical methodology to quantify the losses produced by induced currents in the metallic ducts (throats) used to enclose the bus bars connecting distribution transformers to switchgears. This calculation is important because some transformer manufacturers in Mexico don’t include throats in the load losses measurement. In particular, it presents the results of simulations made with commercial Finite-Element Software, to quantify the stray losses, originated by the induced currents, in throats of a 2000 kVA distribution transformer. The information provided by transformer’s manufacturers has been used judiciously in the creation of the numerical model. © 2012 IEEE.