Army Groups

• 1st Army Group ("phantom" formation)
• 6th Army Group - Western Europe
• 12th Army Group - Western Europe
• 15th Army Group - Italy

Field Armies

• First Allied Airborne Army (inactive)
• First United States Army (Mobilization, Readiness & Training Command)
• Second United States Army (inactive)
• Third United States Army (United States Army Central)
• Fourth United States Army (inactive)
• Fifth United States Army (United States Army North)
• Sixth United States Army (United States Army South)
• Seventh United States Army (United States Army Europe)
• Eighth United States Army
• Ninth United States Army (United States Army Africa)
• Tenth United States Army (inactive)
• Fourteenth United States Army ("phantom" formation)
• Fifteenth United States Army (inactive)

US armies by theater

Europe:

• First United States Army
• Third United States Army
• Fifth United States Army
• Seventh United States Army
• Ninth United States Army
• Fifteenth United States Army

Pacific:

• Sixth United States Army
• Eighth United States Army
• Tenth United States Army

USA:

• Second United States Army - training units in the Eastern US
• Fourth United States Army - training units in the Western US

Corps

Army:

• I Corps
• II Corps
• III Corps
• IV Corps
• V Corps
• VI Corps
• VII Corps
• VIII Corps
• IX Corps
• X Corps
• XI Corps
• XII Corps
• XIII Corps
• XIV Corps
• XV Corps
• XVI Corps
• XVIII Airborne Corps
• XIX Corps
• XX Corps
• XXI Corps
• XXII Corps
• XXIII Corps
• XXIV Corps
• XXXIII Corps ("phantom" formation)
• XXXVI Corps

Marines:

• III Amphibious Corps
• V Amphibious Corps

US corps by theater

Europe:

• II Corps
• III Corps
• IV Corps
• V Corps
• VI Corps
• VII Corps
• VIII Corps
• XII Corps
• XIII Corps
• XV Corps
• XVI Corps
• XVIII Airborne Corps
• XIX Corps
• XX Corps
• XXI Corps
• XXII Corps
• XXIII Corps

Pacific:

• I Corps
• IX Corps
• X Corps
• XI Corps
• XIV Corps
• XXIV Corps
• III Amphibious Corps
• V Amphibious Corps

USA:

• XXXVI Corps