Exemplary embodiments wet-on-demand dispensers are disclosed herein. An exemplary dispenser for dispensing wet-on-demand substrates includes a housing, a container for holding a fluid, one or more wetting tips in fluid communication with the container. Each of the one or more wetting tips has a movable valve member. The exemplary dispenser further includes a holder for holding a roll of substrate and the movable valve members are moved as a function of contact with the substrate.