Several studies have shown that finishing bulls kept in housing systems with fully slatted concrete floors are impaired in their lying behaviour and locomotion due to the hardness and slipperiness of the ground. The aim of this study was to investigate the effects of floor quality (straw-bedded lying area, rubber-coated slats, concrete slats) on the lying behaviour of finishing bulls. The floor type did not influence the total lying duration, but the number of lying bouts and the number of short standing periods decreased with increasing hardness of the floor in the lying area. In addition, bulls showed more interrupted lying-down and standing-up movements on concrete and rubber-coated slats than on straw bedding. On the other hand, atypical lying-down and standing-up instances, slipping and falling were reduced on rubber-coated slats and on straw bedding compared to concrete slats. Displacements of lying animals were observed more often on rubber-coated slats than on concrete slats or straw bedding. In conclusion, rubber-coated slats improve traction on the ground but are not able to provide as soft a lying area as straw bedding. Rubber coating can thus serve to improve welfare for finishing bulls kept on concrete slats but cannot be considered equivalent to straw bedding.