The BBC's veteran ballroom dancing show - which returned with 8m on Friday - soared to an average of 8.72m (40.7%) between 6.30pm and 7.45pm, waltzing to a peak of 10.2m in the last five minutes.
The X Factor, airing for two-and-a-half hours from 8pm until 10.30pm, attracted 8.68m (33.9%) to ITV for its first live show - peaking with less than 10m at around 9pm.
However, the singing contest added 380k (1.9%) on ITV1 +1, and The Xtra Factor followed on ITV2 with 486k (2.9%). On the same night last year, The X Factor was 2.2m ahead of Strictly in the ratings.
Elsewhere, the series five premiere of Merlin, which partly clashed with The X Factor, scored an impressive 5.49m (23.5%) for BBC One.
Paddy McGuinness's cult dating show Take Me Out returned with 3.12m (14%) at 7pm and 233k (1%) an hour later on timeshift. Before Take Me Out, Fool Britannia had 2.02m (10.3%) and 224k (1%) on +1.
The Jonathan Ross Show pulled in 2.94m (18.8%) from 10.30pm (+1: 226k/2.6%), losing out to BBC One's Match of the Day which netted 3.4m (24.9%).
Also on BBC One, The National Lottery: Secret Fortune (3.48m/15.2%) and Casualty (3.82m/16.8%) put in respectable performances later on against The X Factor.
Predictably, Dad's Army was BBC Two's best-rated programme of the night with 1.88m (8.2%) at 7.30pm, while Channel 5's movie The Battle of Britain fetched 1.04m (4.5%), and The Million Pound Drop Live was Channel 4's most-watched broadcast with just 663k (3%) from 9pm (+1: 123k/0.7%).
Overall, ITV1 managed a convincing primetime victory over BBC One with 29.9% (+1: 1.4%) versus 23.8%. Far behind the top two, BBC Two claimed third place with 5.4%, ahead of Channel 5's 4.1% (+1: 0.1%), and Channel 4's 2.8% (+1: 0.4%).
BARB ratings data supplied by Attentional