Doctor Who: Revolution of the Daleks had a final official rating of 6.25 million viewers.
The final rating takes into account all those who recorded the programme and watched it within one week.
The rating confirms Doctor Who as the top-rated BBC One programme for New Year's Day, beating EastEnders which had 4.36 million watching and Mrs Brown's Boys with 4.87 million.
Overall Doctor Who was second for the day, with Coronation Street just claiming the top spot with 6.39 million viewers.
Doctor Who is likely to finish the week as the 8th most-watched programme, the same position held by the New Year 2020 programme SpyFall.
The most-watched programme for the week ending 3rd January was Happy New Year Live! with 9.92 million watching London mark the start of 2021.