23rd Battalion may refer to: 23rd Reserve Battalion, CEF, an infantry unit in the Canadian Expeditionary Force during the First World War 23 Service Battalion, a Combat Service Support unit of The Canadian Forces Reserve since 1965 23rd Battalion (Australia), an infantry battalion of the Australian Army that served in World War I 2/23rd Battalion (Australia), an infantry battalion of the Australian Army that served in World War II 23rd Battalion (New Zealand), a World War II infantry battalion