Little is known of the early history of the settlement after the Hungarian conquest. The name originates from the name of one of the Kabar tribes that joined the Hungarians.
The first written mention of Örs dates from 1236 when Béla IV, king of Hungary donated a church together with the St. Martin chapel to the Cistercians. Under the Turkish occupation during Ottoman rule the area was uninhabited and was resettled by Schwab peasants in the early 18th century by the countess Zsuzsanna Bercsényi.
Since then the town developed rapidly. While at the end of the 18th century only 1143 peasants lived here, in 40 years the number tripled. The World Wars affected the town badly; and after the war it was Budaörs where the Communist government begun forcing ethnic Germans to leave their homes.
As of 2009[update], Budaörs had a population of 26,400.