The following article lists four Orders of Battle for the Iranian Army at different periods. Note, that this is not the order of battle of the Iranian Revolutionary Guard Corps but of the regular ground forces (Artesh).
Army Order of Battle (Localities) First Army Headquarters Tehran Second Army Headquarters Esfahan Third Army Headquarters Shiraz 28th Mechanized Division Kerman 35th Mechanized Division Khorramabad 84th Mechanized Division Shiraz 2nd Armoured Division Dezful 16th Armoured Division Qazvin, Qasr-e Shirin region 18th Armoured Division Tehran 81st Armored Division Kermanshah 88th Armoured Division Ahvaz 92nd Armoured Division Khuzestan 30th Infantry Division Tehran 40th Infantry Division Hamadan 21st Infantry Division Azerbaijan 64th Infantry Division Urumia 77th Infantry Division Khorasan 1st Marine Brigade Bandar Abbas 79th Infantry Division Tabriz 84th Infantry Division Lorestan 23rd Special Forces Division Tehran 55th Parachute Division Shiraz 351st SSM Brigade Tehran 75th Logistics Brigade 22nd Artillery Division 23rd Artillery Division 44th Artillery Division Esfahan 55th Artillery Division Esfahan
Army Order of Battle, c. 1998 Southern Operations Sector(Dezful) Northern Operations Sector (Rezaiyeh) Western Operations Sector (Kermanshah) 81st/92nd? Armored Division 28th Mechanized Infantry Division 16th/18th? Armored Division 45th Commando Brigade 64th Infantry Division 81st Armored Division 40th Infantry Brigade 84th Mechanized Infantry Division 25th Commando Brigade 23rd Commando Division 11th Artillery Division 35th Commando Brigade 58th Commando Brigade 22nd Artillery Division 23rd Artillery Division 44th Artillery Division 55th Artillery Division 411th Engineer Division Eastern Operations Sector (Birjand) Airmobile Forces Group 88th Armored Division 29th Commando Division (Airmobile) 30th Infantry Division 55th Airborne Division 77th Infantry Division Sources: Bomba, Ty "Back to Iraq: Speculations on Gulf War II" (Issue 50, 1998). Liebl, Vern "The Iranian Armed Forces Today. (Issue 41, 1998).
Imperial Army Order of Battle, c. 1970s 16th Armored Division Ghazvin 81st Armored Division Kermanshah 92nd Armored Division Khuzestan 88th Armored Division Sistan 1st Infantry Imperial Guard Division E. Azarbaijan (21st Infantry Div. after the Revolution) 2nd Imperial Guard Division E. Azarbaijan (21st Infantry Div. after the Revolution) 28th Infantry Division Kurdestan 30th Infantry Division Golestan 64th Infantry Division (Iran) W. Azerbaijan 77th Infantry Division Khorasan 84th Infantry Division Lorestan 55th Airborne Brigade Fars (Division during the war with Iraq) 65th Airborne Brigade Tehran (Division during the war with Iraq) 23rd Airborne Brigade (NOHED) Tehran (Division during the war with Iraq) 37th Armored Brigade Fars 11th Artillery Group E.Azarbaijan 22nd Artillery Group 33rd Artillery Group Tehran 44th Artillery Group 55th Artillery Group 99th Air Defence Group 4 Hawk missiles Battalions Source:
Divisions of the Ground Forces, 1941 Source: https://fa.wikipedia.org/wiki/نیروی_زمینی_شاهنشاهی_ایران The divisions of the Ground Forces at the time of the Allied invasion of 1941 were as follows:
Central 1st Division: Includes 4 infantry regiments, 3 cavalry regiments, 2 mountain artillery regiments, and several engineering battalions. The talent of 13,000 people.
2nd Central Division: includes 3 infantry regiments, 3 cavalry regiments, 2 artillery regiments, and several engineering battalions. Talent: 12,000.
Tehran Independent Mechanized Brigade. Includes a light tank battalion with a capacity of 50 tanks. A medium tank battalion with a capacity of 50 tanks.
3rd Northeast Division: Includes 3 infantry regiments, 2 cavalry regiments, 1 artillery regiment, and 1 air regiment. Talent: 9,500 people.
4th Northwest Division: 1 infantry regiment, 2 cavalry regiment, 1 artillery regiment. Talent 4500.
5th Kurdistan Division: includes 3 infantry regiments, 1 cavalry regiment. 5,000 people
6th Division of Khuzestan: includes 3 infantry regiments, 1 cavalry regiment, 1 artillery regiment, and 1 air regiment. 8,000 people.
7th Fars Division: including 3 infantry regiments, 1 mixed artillery regiment, and 1 cavalry regiment. The talent of 5,000 people.
8th Division of Kerman: includes 1 infantry regiment, 1 cavalry regiment, and 1 mixed artillery regiment. The talent of 4,500 people.
9th Khorasan Division: Includes 2 infantry regiments, 2 cavalry regiments, 1 mixed artillery regiment, and 1 air regiment. Talent: 6,000 people.
10th Gorgan Division: Includes 1 infantry regiment, 1 cavalry regiment, and 1 artillery regiment. The talent of 4,500 people.
The 11th Division of Gilan: It includes 3 infantry regiments. Totalled 4,000 people.
12th Division of Kermanshah: 1 infantry regiment, 1 cavalry regiment, 1 field artillery regiment, 1 mixed mountain regiment. Totalled 4,000 people.
Isfahan 13th Division: Commanded by Fazlollah Zahedi. Includes 1 infantry regiment, 1 cavalry regiment, and 1 artillery regiment. The talent of 4,000 people.
The 14th Makran Division: Includes 2 infantry regiments, 1 cavalry regiment, 1 artillery regiment, and 1 Jammaz (camel) battalion. The talent of 4,000 people. Former Makran Brigade
15th Division of Ardabil: 2 infantry regiments, 1 cavalry regiment. The talent of 4,000 people.
16th Lorestan Division: 1 infantry regiment, 1 cavalry regiment, 1 artillery battalion. The talent of 4,000 people.
17th Khoy Division: 1 infantry regiment, 1 cavalry regiment. The talent of 3,000 people.
18th Torbat-e-Jam Division: 3 infantry regiments. The talent of 4,000 people.
Total: 94,000 soldiers.
References
https://cgsc.contentdm.oclc.org/digital/api/collection/p15040coll6/id/4164/download - partial order of battle October 1940