A crowd of almost 20,000 saw Wigan get the victory they needed to pip Ipswich to the second promotion spot and make it a dream come true for everyone at the club.
The Latics virtually had the game sewn up at the break, with two goals in two minutes from Lee McCulloch and Jason Roberts putting them in control, and when Nathan Ellington added a third with five minutes left the party began in earnest.
David Kitson's consolation goal deep into injury time failed to spoil the party and for Reading it was a day of disappointment as defeat meant they missed out on the final play-off spot.