The textile industry releases highly polluted and complex wastewaters, which are difficult to treat and require numerous treatment steps. Innovative technologies for on-site treatment at each factory would permit cost reduction. For this reason, we ran a laboratory-scale study to assess the suitability of a sequencing batch biofilter granular reactor (SBBGR) for textile wastewater treatment, testing four different types of wastewater. Results demonstrate that wastewater characteristics greatly affect the reactor efficiency. Hence, a pre-study is advisable to define the best operational conditions and the maximum treatment capability for the wastewater under analysis. Nevertheless, SBBGR is a valuable biological treatment, effective in the reduction of pollutant load with stable performances despite the variability in wastewater composition. Tests with ozone integration have demonstrated that it is possible to dose small quantities of ozone to obtain an effluent suitable for direct discharge. However, a dynamic ozone dosage should be used to optimize the process as the correct ozone dose strongly depends on the wastewater composition.