The 2nd Battalion, 503rd Infantry Regiment (2-503rd IR) is an active duty airborne infantry battalion in the United States Army, assigned to the 173rd Airborne Brigade Combat Team and stationed at , Vicenza, Italy. The battalion has served with the 2nd Infantry Division, the 11th Airborne Division, the 24th Infantry Division, The 25th Infantry Division, the 82nd Airborne Division, the 101st Airborne Division, and the 173rd Airborne Brigade; has been stationed in Korea, Germany, Italy and the United States; and earned campaign credits in World War II, the Vietnam War, Operation Enduring Freedom-Afghanistan, and Operation Iraqi Freedom.