The third classification was the mountains classification. Points were awarded to the riders that reached the summit of the most difficult climbs first. The climbs were categorised, in order of increasing difficulty, as fourth-, third-, second-, and first-category and hors catégorie. Double points were awarded at the top of the last mountains in the three mountain stages in the three Pyreneean stages (the Col du Portillon, the Col de Portet and the Col d'Aubisque). The leader wore a white jersey with red polka dots.