Which Unicode characters combine in pairs to form many flag emoji?

Regional indicator symbols combine in pairs to form many flag emoji.

Unicode’s regional indicator symbols are 26 alphabetic characters corresponding to A through Z. When two are placed together in a recognized sequence, they can be rendered as a flag emoji based on a two-letter regional code, such as 🇺🇸 for US or 🇯🇵 for Japan.

This design avoided encoding a separate Unicode character for every national flag. Instead, the standard uses a reusable mechanism tied largely to ISO 3166-1 alpha-2 codes and related region data. The characters were introduced as part of Unicode’s emoji support around Unicode 6.0, finalized in 2010.

A common mix-up is assuming every pair of the 26 symbols becomes a flag. Mathematically there are 676 possible ordered pairs, but platforms recognize only a defined subset as valid emoji flag sequences. Regional flags such as England, Scotland, and Wales use a different tag-sequence mechanism rather than ordinary two-symbol country flags. Rendering also depends on the operating system or application.