|Use||National flag and ensign|
|Adopted||21 September 1981 (standardized on 28 August 2019)|
|Design||A royal blue field with two red narrow horizontal stripes along the top and the bottom edges and the large white disk in the centre bearing the National Coat of Arms.|
British Honduras obtained a coat of arms on 28 January 1907, which formed the basis of the badge used on British ensigns. The coat of arms recalls the logging industry that first led to British settlement there. The figures, tools, and mahogany trees represent this industry. The national motto, Sub Umbra Floreo, meaning "Under the Shade I Flourish", is written in the lower part of the coat of arms.
The flag is royal blue, with a white disc at the centre containing the national coat of arms held by a mestizo and a man of African descent. The flag of Belize is the only country to have humans depicted as a major design element on its national flag, although the flag of Malta contains an image of Saint George on the badge of the George Cross, and the flags of British overseas territories Montserrat and the Virgin Islands, and that of French Polynesia also depict humans.  Several other countries' flags have human body parts depicted. The flag of Brunei has human hands, and the flags of Uruguay and Argentina both have human facial features depicted in a personified sun.
The flag is bordered at top and bottom by two red stripes. In all, the flag incorporates 12 different colours and shades, making it the most colourful national flag in the world.
The colours on the flag are respectively those of the country's national parties, the People's United Party (PUP), and United Democratic Party (Belize) (UDP). The UDP, established in 1973, had objected to the original blue and white design, those two colours being the PUP's representative colours.
The two red stripes at the top and bottom were added to the original design at independence. The coat of arms was granted in 1907. Red stripes were added to denote the colour of the opposition party. The 50 leaves recall 1950, the year PUP came to power.
From 1950 onward, an unofficial national flag was in use. It was blue, with the coat of arms on a white disc in the centre (sometimes a blank white circle was used as the coat of arms was difficult to draw).
In 1981, Belize gained its independence and a competition was held to design a national flag for the country. The winning submission consisted of the unofficial national flag used by the People's United Party with a red border added to all four sides. This was changed to a red border on just the top and bottom before the design was officially adopted. The winning design, which was also known as the "Flag of Unity" was made by two government officials: Everal Waight, Public Secretary, and Inez Sanchez, Chief Education Officer.
There were no standardized specifications for the flag of Belize until 2019. The hue of the flag's colours, proportions, the shading of the two men, and other elements often varied. In 2019, the National Celebrations Commission started a standardization process of the flag with consent from both the PUP and the UDP. They planned to have the standardized flags be hoisted on September 1, 2019, the National Flag Day of Belize. There are plans to formalize the standardization through national legislation.
- "Belize Flag, Coat of Arms". Retrieved 22 August 2015.
- "Waight, Sanchez Win National Flag Competition". The Voice. 1 (6). August 7, 1981.
- "A Standardized Belizean Flag". Guardian. 30 August 2019. Retrieved 27 December 2019.
- "Belizean Flag Standardization Presentation". Ambegris Today. 29 August 2019. Retrieved 27 December 2019.