The RDF-produced show kicked-off with 3.3m (13.9%) and steadily grew to 3.9m (16.9%) in the final 15 minutes. It failed to match the channel's slot average of 4.4m (18.8%) for last year.
Last time the Pygmalion-style makeover show aired, in 2006, the final pulled in a much more respectable 5.3m (23.9%) in a similar 9pm slot.
This year's five-part run averaged a disappointing 3.6m (15.2%) although its audience was fairly loyal with its audience only fluctuating by 400,000 over its run. The most popular show drew 3.8m (16.2%) on 5 February.
The series drew in a healthy amount of ABC1 viewers with 41.5% of the audience coming from that demographic. ITV executives will be concerned about its lack of appeal to younger viewers as only 5.6% of its audience were made up of those aged between 16 and 34.
In 2006, the series gained an average of 4.6m (21.7%) with its least popular edition picking up 4.3m (20.3%).
Last night's final felt the pressure from strong performances from BBC2, Five and BBC1.
BBC2's science strand Horizon gained 3m (12.6%) for Prof Regan's Supermarket Secrets over 50-minutes while just ahead of BBC2 was Five's CSI: Crime Scene Investigation, also at 9pm, with 3.1m (13.1%) for an hour.
Comfortably taking the spoils at 9pm though was BBC1's Hotel Babylon with a robust 5.4m (22.9%), holding a steady audience throughout.
Channel 4 was effectively out of the running at 9pm with The Woman Who Stops Traffic failing to make much of an impression. The first 60-minute show in a three-part run interested just 1.1m (4.7%), substantially down on the channel's slot average of 2.7m (11.6%). A further 47,000 viewers saw the show on C4+1.
BBC1 had a clear lead over its terrestrial rivals at 8pm once again as Holby City grabbed 6.6m (27.4%) for an hour. ITV1's long-running game show Who Wants to be a Millionaire? managed 4.3m (17.7%).
BBC2 also found itself a popular attraction at 8pm. The ongoing An Island Parish picked up 2.7m (11.5%), followed by Masterchef at 8.30pm on 3.3m (13.6%).
The cookery show although down by a million on Monday's edition was still up on the slot average by a million.
C4 picked up a respectable 2.3m (9.3%) for Supersize vs Superskinny for an hour with a further 149,000 watching on C4+1.
Although Five trailed the terrestrial pack at 8pm with 1.6m (6.8%) for Bermuda Triangle: the True Story the factual show was up by half a million on the channel's slot average.
All hours shares for Tuesday 26 February 2008: BBC1 - 22.2%, ITV1 - 18.9%, BBC2 - 8.6%, C4 - 8.5%, Five - 7.3%, multichannel - 33.9%.
Peaktime (6pm to 10.30pm) shares: BBC1 - 25.8%, ITV1 - 20.4%, BBC2 - 9.8%, C4 - 7.7%, Five - 7.2%, multichannel - 28.7%.