Wing commander (Wg Cdr in the RAF, the IAF, and the PAF, WGCDR in the RNZAF and RAAF, formerly sometimes W/C in all services) is a senior commissioned rank in the Royal Air Force and the air forces of many countries which have historical British influence, including many Commonwealth countries but not including Canada and South Africa. It is sometimes used as the English translation of an equivalent rank in countries which have a non-English air force-specific rank structure. It ranks immediately above squadron leader and immediately below group captain. It has a NATO ranking code of OF-4, and is equivalent to Commander in the Royal Navy and to Lieutenant Colonel in the British Army, the Royal Marines, and the US Army, Air Force, and Marine Corps.
The equivalent rank in the Women's Auxiliary Air Force, Women's Royal Air Force (until 1968), and Princess Mary's Royal Air Force Nursing Service (until 1980) was wing officer. The equivalent rank in the Royal Observer Corps (until 1995) was observer commander which had a similar rank insignia.