Addison is an incorporated town in Dallas County, Texas, United States. The 2020 census population was 16,661. Addison is immediately north of Dallas.

Addison and Flower Mound were the only two Texas municipalities labeled "towns" with a population greater than 10,000 at the 2010 census; since then the municipalities of Prosper and Trophy Club—also identifying as towns—have also exceeded 10,000 in population estimates.

Addison was originally part of Peter's Colony. The future town site was settled as early as 1846 when Preston Witt built a house near White Rock Creek. In 1849, the Witt family opened a gristmill. In 1880, settler Sidney Smith Noell purchased a large tract of land south of what is now Belt Line Road. In 1888, Noell, together with W.W. Julian and W. E. Horten, donated land to the St. Louis, Arkansas and Texas Railway, a predecessor of the St. Louis Southwestern Railway (known as the Cotton Belt), for a coaling station.

The first substantial industry in the community was a cotton gin, opening in 1902. In 1903, the Cotton Belt built a depot and a 12 mi (19 km) branch line leading south to Dallas, named the site Noell Junction, and started passenger train service from the small depot to the city. In 1904, a post office opened; however, there was already a community named Noell in Leon County, Texas, so the new community changed its name to Addison, after Addison Robertson, a local resident who would later serve as the community's second postmaster from 1908 to 1916. Also in 1904, Julian platted the first six city blocks.

The population grew to 75 by 1914, at which time the community had three grocers and a bank, but the bank later failed and the population fell to 40 in 1926. After World War II, residents grew concerned that the nearby cities of Dallas, Carrollton, or Farmers Branch might annex the community, so they petitioned the county to allow an election for incorporation. The election was held on June 15, 1953, and by a vote of 19 in favor and 11 against, Addison was incorporated as a city.

In 1955, W.T. Overton, a 28-year-old businessman from Dallas, purchased a large farm north of the Cotton Belt depot, and in January 1956, he announced that the site would be redeveloped as an airport focused on business aircraft. After obtaining final approval from the city, Addison Airport had its formal groundbreaking ceremony on March 16, 1957, and its grand opening took place on October 18 of that year.

At the time, Addison residents relied almost entirely on private wells for water. Overton and his investors realized that a private well would not support their development plans, so they petitioned the city to drill a municipal well and build its first public water system. The project was approved by voters in April 1957 and construction began in August. The well was later supplemented by a large water main extended from Dallas.

In 1961, an investment group including Overton, John D. Murchison (son of oil magnate Clint Murchison Sr.), and Dallas-area developer Trammell Crow opened a 73-acre (30 ha) industrial park in the triangular area formed by the Cotton Belt, Dooley Road, and the main Addison Airport runway.