Abstract Smart, electronic textiles are often exposed to tensile stress which can lead to fracture of the interwoven conducting yarns. In this study, a model is proposed to relate the extensibility of the conducting yarns to the weaving pattern of the textile – in particular to the thickness and pitch of the textile yarns. The model is validated by simultaneous mechanical and electrical tests on bare yarns extracted from several textiles. The results show that mechanical failure precedes electrical failure. Thus, a lower and conservative bound for electrical failure can be obtained from the extensibility prediction as a function of the structure of the weave.