The flag of Saint Kitts and Nevis consists of two horizontal bands of equal size, the top one is green and the bottom one is red. A black, inverted triangle is centered on the hoist side, bordered in white, with a thin yellow stripe edging the black. The ratio of the flag's height to its width is 3:5. The color codes for the flag are:

• Green: Pantone 355 C / RGB 0 100 60 / CMYK 100 0 70 30
• Red: Pantone 186 C / RGB 206 17 38 / CMYK 0 100 90 10
• Black: Pantone Black C / RGB 0 0 0 / CMYK 0 0 0 100
• White: n/a (no Pantone or CMYK values)

The black triangle has a base width of one-fifth (1/5) of the flag's width, and its height extends to the center of the flag. The yellow stripe is 1/20th of the flag's width, and it borders the black triangle on all sides.