I have 3' tresses and my LUSH shampoo bar lasts a couple of months. (around 50 to 60 showers, sometimes more, less for the shampoo and conditioner bars and for the solid conditioner) It lasts longer if I let it dry a bit and then close the tin (LUSH usually will give you one for free if you buy two of the round shampoo and or conditioner bars). Also, setting it a little out of the shower helps too, as when other people shower it tends to melt if the container is open. The soaps work similarly, and I usually use Altoids tins for those after I cut off a piece that will fit.