Continuous fibers from blends of cellulose acetate butyrate (CAB) with lignin (L) were spun from liquid crystalline solution. Morphological investigations suggest that CAB and L form blends with considerable phase mixing. The porosity of the surface structure of CAB/L fibres increased with increasing L content. The mechanical properties of the L-containing fibres increased with phase mixing of CAB and L molecules in the fibre matrix. This study shows that phase mixing can be enhanced by coagulation during wet spinning.