On Saturday, Simon Cowell's pop competition was beaten in the ratings by Strictly Come Dancing, which notched up 8.59m (40.6%) against its rival's 8.18m (36%).
Last night The X Factor was back ahead, however, as the ballroom-based reality show averaged 8.13m (31.6%) in the 8pm hour. Heartbeat put in an admirable performance at the same time, with 6.1m (23.7%). Up against The X Factor, BBC One's Antiques Roadshow managed 5.96m (25.4%).
ITV1 regained the lead at 9pm with the final instalment of the Poirot story 'The Third Girl'. Starring Zoe Wanamaker and Jemima Rooper, the drama pulled in 5.07m (23.7%) over two hours. BBC One had 4.94m (20.3%) for the penultimate instalment of Tess of the D'Urbervilles in the 9pm hour then 4.29m (20.4%) for the 10pm news bulletin.
Overall, ITV1 had a share of 27.4% in primetime (7pm-11pm), compared to BBC One's 23.3%. The commercial broadcaster was also ahead in all-day share, with 23% versus 17.9%.
BBC Two's Charley Boorman: Ireland To Sydney By Any Means drew a respectable 2.3m (9%) in the 8pm hour, while on Channel 4, Wife Swap entertained 1.25m (4.9%). Five charmed 1.1m (4.3%) with documentary Austin Stevens' Adventures: Giant Python of the Everglades.
At 9pm, new series James May's Big Ideas, following the Top Gear host's quest to find the world's ultimate flying machine, began strongly with 2.93m (12%) for the hour. Five movie Hitch averaged 1.47m (7.5%) between 9pm and 11.25pm, putting the channel ahead of C4's rival film Pan's Labyrinth, which had 1.31m (6.5%) between 9pm and 11.15pm.
Overall, BBC Two had a 9.6% share in primetime. Five rounded out to 6%, ahead of Channel 4's 4.9%.
Repeats helped ITV2 enjoy a strong night in multichannel homes, led by 911,000 (6.1%) for an X Factor rerun from 5.35pm. Spinoff show The Xtra Factor logged 790,000 (3.6%) in the 8pm hour and at 9pm, Katie & Peter: The Next Chapter brought in 539,000 (2.6%).
BBC Three's best audience was 291,000 (1.3%) for The World's Strictest Parents at 8pm, while E4 peaked with 284,000 (1.8%) for first-look Desperate Housewives at 10pm.
FX had an impressive 343,000 (1.6%) for its preview of the new season of NCIS in the 9pm hour, but new drama Breaking Bad, which followed at 10pm, got off to a slow start with just 77,000 (0.5%).
> Friday Ratings: ITV1 wins Friday ratings battle
> Saturday Ratings: 'Strictly' beats 'X Factor'
Ratings data supplied by Attentional