This paper presents the "Serial Water Balance" method for predicting leachate generation in landfills. This procedure makes it possible to calculate the total leachate likely to be generated, by estimating an individual cell by cell water balance. This new development considers the interaction effects between cells, through the execution of simple field capacity tests on solid waste samples under different loading conditions. The procedure described in this paper simulates the effect induced by fluid percolating from a cell at an upper layer to cells in the immediately subjacent layer. The method described here was applied to the landfill in Nuevo Laredo, Tamaulipas (Mexico), after first ascertaining information regarding: duration of construction time, exposure time, surface area, the quantity of waste, number of confining cells, and local weather conditions. In a full-scale test case the suggested method has predicted 67% of the leachate produced in a period of 4 years. Further testing and more detailed analysis of the composition of the waste used in the calculations, may improve the accuracy in predicting leachate production. Even though this SWB methodology was applied to a landfill subject to extreme climatological conditions (high daytime temperatures), it is possible to adapt the methodology to solid waste disposal sites in regions with more humid or moderate climates.