Wolves will be playing Premier League football next season after their promotion from the League Championship was confirmed with a 1-0 win over QPR at Molineux.
As he has been throughout the season, top-scorer Sylvan Ebanks-Blake was the hero of the hour once again for Mick McCarthy's side, slotting Andy Keogh's pass home a minute after the break for his 25th goal of the season.
Wolves had to ride their luck at times as the visitors applied the pressure in the second half, but the league leaders held firm to secure their ticket to the top flight next season.
Birmingham remain in the second automatic promotion spot and moved four points clear of third-placed Sheffield United after Cameron Jerome's late winner gave them victory at Watford.
Cardiff stay in fourth but their hopes of making automatic promotion took a major blow after they were hammered 6-0 at Preston, who revived their own hopes of making the play-offs.
North End are now just a point away from the top six after a Neil Mellor brace, strikes from Jon Parkin, Chris Brown and Lee Williamson and a Mark Kennedy own goal giving them a crushing win at Deepdale.
Swansea also kept their play-off hopes alive with a 1-0 win over Bristol City, Garry Monk heading in at the near post from a corner on 25 minutes to give Roberto Martinez's side all three points.
Reading are still fifth after a disappointing goaless draw at the Madejski Stadium with Barnsley, who are a point above the relegation zone.
At the bottom, Charlton were relegated to League One after letting a two-goal lead slip at home against Blackpool.
The Addicks appeared to be going down fighting after Deon Burton and Jonjo Shelvey scored a minute apart straight after half-time.
But DJ Campbell pulled a goal back from the penalty spot for the visitors with just over 20 minutes remaining before substitute Lee Hughes sealed Charlton's fate with an equaliser in stoppage time.
Things also look grim for second-bottom Southampton after a Luke Varney brace condemned them to a 2-0 defeat at Sheffield Wednesday which leaves the Saints three points from safety with two games to play.
Nottingham Forest moved out of the bottom three and up to 20th with a 1-0 victory over Coventry courtesy of James Perch's winner a minute after the break.
Elsewhere, Crystal Palace beat Derby 1-0 despite having Victor Moses sent off, while Doncaster ran out 3-0 winners at Plymouth.