Allen and Plano are two suburbs of Dallas, Texas. ALLEN is located in Collin County and Plano is located in both Collin and Denton counties. Both suburbs are considered part of the Dallas-Fort Worth metropolitan area and are home to many businesses and attractions. ALLEN is known for its historic downtown district and Plano is known for its shopping and entertainment options. Both suburbs offer a variety of housing options and are popular destinations for families and young professionals.