| Unit Name: | 231st Battalion, CEF |
| Dates: | 1916–1917 |
| Country: | Canada |
| Branch: | Canadian Expeditionary Force |
| Type: | Infantry |
| Specialization: | --> |
| Garrison: | Vancouver, British Columbia, Canada |
| Garrison Label: | Mobilization headquarters |
| Motto: | Gaelic; Scottish Gaelic: Cuidich'n righ|lit='Help the King' |
| Colours: | --> |
| Colours Label: | --> |
| Battle Honours: | The Great War, 1917 |
| Commander1: | Lieut-Col. Francis Easton Leach |
| Commander1 Label: | Officer commanding |
The 231st Battalion, CEF was a unit in the Canadian Expeditionary Force during the First World War. Based in Vancouver, British Columbia, the unit began recruiting in early 1916 in that city and the surrounding district. After sailing to England in April 1917, the battalion was absorbed into the 24th Reserve Battalion on April 22, 1917. The 231st Battalion, CEF had one officer commanding: Lieutenant-Colonel Francis Easton Leach.[1] The battalion is perpetuated by the Seaforth Highlanders of Canada.
In 1929, the battalion was awarded the theatre of war honour "The Great War, 1917".[2]