An electrowetting display device includes a first substrate comprising a wall pattern surrounding a pixel electrode disposed in a display area of the first substrate, a spaced apart second substrate comprising a common electrode and a dam member disposed in a peripheral area surrounding the display area. The dam member has sealable openings (a.k.a. sealable dam spillways) through which there is discharged an excess portion of an excessively supplied wetting layer, the discharge of the excess occurring while the first and second substrates are brought together about top and bottom portions of a sealing ring that seals them together.