Allen is a city in Collin County, Texas, in the northern Dallas–Fort Worth metroplex, situated along U.S. Highway 75 directly north of Plano and roughly 25 miles northeast of downtown Dallas. Its population was 104,627 at the 2020 census, making it one of Collin County's major cities. The community grew from a small railroad and farming town into a large, family-oriented suburb as the Dallas area expanded northward through the late 20th century. Education is a defining feature of Allen. Allen Independent School District serves the city with a network of more than 20 campuses, anchored by Allen High School, one of the largest high schools in Texas, and the 18,000-seat Eagle Stadium. The district's reputation and facilities are a central draw for families moving to the area. The city's commercial landscape is anchored by Watters Creek at Montgomery Farm, a mixed-use outdoor district of shops, restaurants, and green space, along with Allen Premium Outlets and The Village at Allen. These destinations, combined with neighborhood retail, give Allen a self-contained suburban lifestyle while Plano's Legacy West and Frisco's employment centers sit a short drive away. Housing spans early-1990s traditional brick homes, established neighborhoods on the eastern side of the city, and newer master-planned communities with larger homes on the western side. Parks such as the 97-acre Celebration Park, the Allen Event Center, and a growing trail system support recreation and community events. For commuters, US-75 provides the primary route south to Dallas, while Highway 121 and the Sam Rayburn Tollway connect east-west, making Allen a practical base for households working across Collin County and the metroplex. The result is a polished, family-centric suburb that pairs strong schools with convenient access to the region's jobs and amenities.