According to a press release, £4,402,371 of sales were recorded on Monday (9 September) when tickets went on sale - £1.2 million through third party agent Encore Tickets.
Ashley Herman of Encore said, "I am delighted that Miss Saigon will be returning to London in 2014. This is a highly anticipated event and is proving to be a massive draw to our customers around the world."
The previous West End record holder was The Book of Mormon, which took £2.1million when it opened back in March.
Miss Saigon runs at the Prince Edward Theatre from 3 May to 25 October 2014, directed by Laurence Connor, who reconceived the Alain Boublil and Claude-Michel Schonberg musical for its UK and international tour. Connor also reworked Boublil and Schonberg's Les Miserables (with James Powell) for its 25th anniversary tour.
The show story tells the tragic tale of young bar girl Kim, orphaned by the Vietnam war, who falls in love with an American GI called Chris - but their lives are torn apart by the fall of Saigon.
Following the success of last year's film adaptation of Les Miserables, Miss Saigon is also being developed for the big screen.