Cover window having curved corner portion and display device including the same

A cover window includes: a flat portion including in a top plan view, first and second sides respectively extending in first and second directions; a top curved portion contacting the first side and extending therefrom in the second direction; a left curved portion contacting the second side and extending therefrom in the first direction; and a first corner curved portion which connects the top and left curved portions to each other. In cross-section, the first corner curved portion includes: and a bottom end surface which connects inner and outer surfaces to each other, in the top plan view, the bottom end surface includes: a central portion having a first width, and a peripheral portion which is disposed outside the central portion in the first and second directions, the peripheral portion having a second width smaller than the first width.