Flag of Tretrid
 | |
| Name | King Ælfric's Flag |
|---|---|
| Use | National flag, civil and state ensign |
| Proportion | 2:3 |
| Adopted | 1255 |
| Design | Quarterly, the first and fourth quarters, green, the second and third quarters, blue, with a white cross overall. |
| Designed by | Ælfric I |
 Variant flag of the Kingdom of Tretrid | |
| Use | Naval ensign |
| Proportion | 5:3 |
The flag of Tretrid, also known as King Ælfric's Flag, is the national flag of Tretrid.