This study makes part of a broader project to estimate hydrological balances all over the country, at a spatial scale of 5 minute-arc. Several methods are implemented to estimate long-term evaporation over Colombia, such as those by Turc (1945), Morton (1982), Penman (1948), and Holdridge (1978). Point estimations are interpolated to obtain regional averages. Results are tested against observed long term average precipitation and runoff for a wide range of catchment sizes. Turc’s methods turned out to give small error despite being dependat only on precipitation and temperature. Morton's method is based upon the energy balance for which radiation data are needed at a high spatial resolution (not available yet), and therefore results exhibited large errors. Penman's method turns out to be an approximation of the Priestley - Taylor method, based on aerodynamical and energy balance equations. This method exhibited small estimation errors. Holdridge’s method is based on the concept of life zones produced results with large spatial variability and large errors. Morton and Penman’s methods exhibited larger evaporation estimated values than those obtained with Turc or Holdridge's, throughout the country. Despite the quality and lack of existence of long-term hydro-climatological data sets, these methods provide a better understanding of both potential and actual evaporation in Colombia.