The present study evaluates the loss in consumer surplus caused by the low degree of competition in the Mexican telecommunication sector which results in relatively high prices, and also leads to lower levels of consumption across the range of telecommunication services. Econometric techniques are used in order to estimate the prices for telecommunication services and the corresponding numbers of subscriptions to telecommunication services that would have been observed in Mexico if there had been more competition in the Mexican telecommunication sector. The estimation relies on cross-country panel data from OECD countries. Estimates are undertaken for mobile and fixed telecommunication services and broadband services. The consumer harm in Mexico is estimated at USD 129.2 billion, or an average of USD 25.8 billion per year in terms of purchasing power parity over the period 2005-09. The latter amount is equivalent to 1.8% of Mexican GDP per year.