The western sector of the Guadix Basin (Betic Cordillera, Spain) hosts a great amount of important macromammal fossil sites. In order to provide these sites with a precise chronostratigraphic frame, a detailed litho-magnetostratigraphic study has been carried out, and an actualized correlation scheme is presented. Magnetostratigraphic data, obtained for three of the stratigraphic sections measured, the sections with the most accurate biochronological information, are added to this scheme. The magnetostratigraphic correlation with the geomagnetic polarity time scale has allowed us to date the most important fossil sites of the studied area. Additionally, this work has led us to determine the age of the boundary between the two most modern genetic units of the continental filling of the basin, and to calculate the sedimentation rates for the basin center and margins in this sector.