Hosted by Steve and Alex Jones, the opening edition of the charity contest - which saw Katie Price and Russell Kane progress to the final - pulled in a hefty 7.56m (32.3%), up 1.3m on last year's Let's Dance For Sports Relief premiere.
The National Lottery: Secret Fortune, presented by Nick Knowles, followed with 6.17m (26.6%) at 8.15pm, an increase of 280k on last week's first episode, after which the latest instalment of Casualty - titled 'Till Death Do Us Part' - grabbed 6.09m (26.8%).
Over on ITV1, the FA Cup's dream tie between Premier League leaders Manchester United and non-league Crawley Town scored an impressive average of 6.12m (30.9%) from 4.35pm (+1: 59k), peaking with 8.09m (35.9%) in the game's final moments.
The much-anticipated match dented BBC One's Total Wipeout, which entertained 4.04m (18.7%) in the 6pm hour.
Hurt by Let's Dance, Harry Hill's TV Burp dipped to 4.44m (18.8%) at 7.20pm (+1: 262k), down 1.4m week-on-week, before Ant & Dec's Push The Button also plummeted, entertaining just 4.51m (19.4%) at 7.50pm (+1: 160k).
At 9pm, 4.23m (18.1%) watched Take Me Out (+1: 125k), then a repeat of Benidorm's series four finale amused 2.95m (15.5%) at 10.20pm (+1: 145k).
Channel 4's screening of X-Men logged 1.08m (4.6%) from 7.15pm (+1: 134k), and 1.97m (8.9%) tuned in for an extended Million Pound Drop (+1: 312k), while BBC Two's schedule of The Unknown Hancock, Faulks on Fiction and The Tudors interested 1.81m (7.8%), 1.08m (4.6%) and 1.47m (7.1%).
Elsewhere, an NCIS double bill had 1.04m (4.3%) and 1.25m (5.4%) from 7.05pm, CSI: Miami took 1.18m (5%) at 9pm, and CSI: NY fetched 1.83m (8.8%) in the 10pm hour.
Overall, BBC One led primetime with 26.1% to ITV1's 17.5% (+1: 0.6%). Channel 4 claimed third place with 6.4% (+1: 0.7%), followed by BBC Two with 6.7%, and Channel 5 with 5.7%.
BARB ratings data supplied by Attentional