The flag of Christmas Island was unofficially adopted in 1986 after being chosen the winner in a competition for a flag for the territory. It was designed by Tony Couch of Sydney, Australia. The flag was made official on Australia Day, 2002 when the administrator of the territory, Bill Taylor, presented the flag to the Christmas Island Shire.
The flag of Christmas Island consists of a green and blue background, split the top left corner to the bottom right. These colours are intended to represent the land and sea respectively. The Southern Cross constellation appears in the bottom left of the flag in the same manner as it appears on the flag of Australia. In the top right, the golden bosun bird (Phaethon lepturus fulvus, one of six races of the white-tailed tropicbird) appears. It is considered to be a symbol of the Island. The last motif appears in the centre of the flag on a golden disc is the map of the island in green. The disc itself was initially only included to offset the green colour of the map but has become linked to the mining industry.