The flag of the Cayman Islands is a British Blue Ensign with the Union Jack in the upper hoist-side quadrant and the coat of arms on a white disc centered on the outer half of the blue field.

Colors:

1. Blue: Pantone 280 C (#00247D)
2. Red: Pantone 186 C (#C8102E)
3. White: (#FFFFFF)

Aspect ratio: 1:2

Geometric properties and measurements:

1. The flag has three vertical stripes, with the left stripe being one quarter of the flag's width occupied by the Union Jack.
2. The coat of arms is placed on a circular white disc with a diameter of half the width of the blue field.

The coat of arms consists of a shield, a crested helm, and a motto scroll. The shield features three green stars representing the three Cayman Islands, a wavy blue and white band symbolizing the sea, and a red lion passant gardant representing the UK. The crested helm features a green turtle on top of a twisted rope of gold and blue, and a pineapple. The motto scroll beneath the shield reads "He Hath Founded It Upon The Seas."