| 21st Battalion | |
|---|---|
| Active | 1939–45 |
| Country |  New Zealand |
| Branch | New Zealand Military Forces |
| Type | Infantry |
| Size | ~700–900 personnel |
| Part of | 5th Brigade, 2nd New Zealand Division |
| Engagements | Second World War |
| Commanders | |
| Notable commanders | Neil Macky John Allen |
The 21st Battalion was an infantry battalion of the New Zealand Military Forces that served during the Second World War. Formed in January 1940, it was part of the 5th Brigade, 2nd New Zealand Division of the 2nd New Zealand Expeditionary Force. The battalion saw action in Greece, Crete, North Africa and Italy before it was disbanded in December 1945.