The Celebrity Traitors is already the UK's most-watched TV show of the year, even before the final on Thursday night - but just how high could its ratings go?
Audiences for the first four episodes of the tense BBC One game show averaged 12.6 million, according to official seven-day consolidated figures published by the research body Barb.
This includes all people who recorded or watched the programme up to a week after its transmission, along with those who viewed on tablets, PCs and smartphones, and is the standard measure of TV ratings in the UK.
Episode one had been seen by 12.5 million viewers after seven days, with 11.9 million for episode two, 13.2 million for episode three and 12.9 million for episode four, suggesting the show has been slowly gaining viewers over time.
If this trend continues - and consolidated figures for episode five onwards have yet to be published by Barb - then a figure of 14 or even 15 million for the final is not impossible.
A similar rise in viewers took place during the most recent series of the non-celebrity version of The Traitors, which was broadcast on BBC One in January.
Here, the average seven-day audience rose from 9.0 million in week one of its four-week run to 9.2 million in week two, 9.4 million in week three and 9.7 million in the final week.
Some 10.0 million people saw the last episode of this series: high enough to rank it the most-watched TV programme of 2025, until the start of The Celebrity Traitors.
No other show this year has come close to matching either The Traitors or The Celebrity Traitors in terms of ratings.
It is extremely rare nowadays for any television programme - outside of live news or sport - to attract a seven-day audience of 12 million or more.
There were only two instances of this happening in 2024: the final episode of the comedy series Gavin & Stacey (19.3 million) and the feature-length animation Wallace & Gromit: Vengeance Most Fowl (17.1 million).
Both of these were broadcast on BBC One on Christmas Day.
There is an additional measure of TV viewers produced by Barb that estimates the average audience for programmes 28 days after transmission.
While the seven-day measure has been in existence since the 1980s, the 28-day measure was introduced just over a decade ago and figures have been made public only periodically.
How much of a boost in ratings a programme receives between the seven-day mark and 28 days is hard to predict.
For example, ratings for the final episode of The Traitors in January showed only a slight increase, from 10.0 million after seven days to 10.4 million after 28 days.
The launch episode of the latest series of The Great British Bake Off on Channel 4 in September enjoyed a bigger jump, from 7.3 million after seven days to 8.7 million after 28 days.
Given the time taken to compile and process the data, 28-day ratings for The Celebrity Traitors are unlikely to be published by Barb until towards the end of the year.
Source: Press Association
