This paper examines the diffusion pattern of mobile telephony in Colombia. The empirical modelling approach adopted in the paper starts off by choosing between the two functional forms that are most frequently used in the literature, namely the Gompertz and the Logistic models. After applying a formal statistical test to choose the preferred functional form, the evidence suggests that the pattern of diffusion can be best characterised as following a Logistic model. The findings also suggest that despite the fact that in recent years the rate of growth of mobile phone subscribers has started to slow down, there still appears to be room for further expansion as the saturation level is expected to be reached in 2013. The estimated saturation level is consistent with some individuals possessing more than one mobile device.