The official flag of the Republic of Costa Rica is based on a design created in 1848. The state/national flag, also used as the military ensign, includes the coat of arms of Costa Rica. The civil ensign, commonly used as an unofficial national flag, omits the coat of arms.
The flag was officially adopted on November 27, 1906, including a slight modification to the placement and design of the entrenched coat of arms. The flag was updated to reflect concurrent modifications to the national coat of arms in 1964 and 1998