Although it was not named in the Domesday Book, a number of neighbouring areas, such as Dunham were. At this time Alfward had an estate embracing modern day Dunham, Ashley and Baguley. In Norman times the area came under Hamo of Masci, whose base was initially a wooden castle at Dunham. By 1286 the fifth Hamo, still based at Dunham Castle, was assisting Edward I against the Scots. It was Hamo who obtained for Altrincham its charter as a borough in 1290 and this charter was renewed in 1319. The last of the line of Hamos died in 1342 and the Black Death decimated the area in 1348. In 1494 the ruins of the castle at Dunham were acquired by Robert Booth, whose family was subsequently ruined in the Civil War (c.1640). By 1750 the estate had passed to the Stamford family.

There are relatively few historical remains evident in the town today. The oldest surviving part of the town is that around the Old Market Place and Church Street (on the A56). It was here that Bonnie Prince Charlie's troops were allegedly billeted in 1745. A number of Georgian buildings also survive in this area on High Street. Altrincham's fortunes improved with the arrival of the famous Bridgewater Canal, constructed in the 1760s and this can be seen most conveniently from the A56 at Broadheath Bridge. In the latter part of the 18th century the town had a cotton and worsted trade but it was the opening of the Manchester South Junction and Altrincham Railway (MSJA) in 1849 which really prompted the town's growth. Also in 1849 the first Town Hall was established adjacent to the Unicorn Hotel. Altrincham endured epidemics of typhoid and cholera in the 19th century but in the latter part of the century many prosperous Manchester businessmen took up residence, particularly in Bowdon, at the southern edge of Altrincham. From here they commuted to Manchester by train. The existing town hall buildings were erected in 1900 and in 1937 Altrincham became a Municipal Borough. In the 1890s the Broadheath area started to become heavily industrialised.From the 1970s Altrincham's industrial base declined and the area is now predominantly residential and commercial in nature.

The town became part of Trafford Metropolitan Borough in 1974 having, till then, been part of the County of Cheshire. Indeed, postally, the town's address is still "Altrincham, Cheshire". The more northerly part of the town includes the formerly industrial area of Broadheath, which lies to the west of the A56 on the Bridgewater Canal. To the east lies the more residential area of Timperley. The Broadheath area developed boomed in the early 20th century as a major industrial complex, with factories of such firms as Linotype George Richards, and Budenberg Gauges. Today, most of the town's heavy industry has disappeared and much of Broadheath is now a retail park, housing Homebase, B+Q, Aldi and other national stores. The railway links have also declined, with Altrincham now served only by an hourly service to Chester and Manchester (via Stockport). Other railway lines, through the former stations at West Timperley and Broadheath, have been closed to passengers for years and the latter line was irrevocably severed in the late 1990s to facilitate the building of the new Altrincham Retail Park. However, on a positive note, the MSJA has been replaced by Metrolink trams which link the town, via Sale, Stretford and Old Trafford to Manchester and Bury. But underfunding means that Metrolink is overcrowded, expensive and has poor-quality track work, especially on the stretch between Dane Road and Stretford.