The singer's comeback track, which was unveiled yesterday morning, is number one on iTunes in both countries.
The position means it is likely to top the Official Chart in the UK this Sunday and make an impressive start on the Billboard Hot 100.
Billboard reports that 'Suit & Tie' is on course to have the biggest sales week for a download since Taylor Swift's 'I Knew You Were Trouble', and is estimated to sell over 400,000 copies in seven days. Swift sold 416,000 units in October 2012.
Timberlake's previous best US sales week was for 'SexyBack', where it shifted 250,000 downloads in September 2006.
It was recently reported that searches for Justin Timberlake concert tickets had soared since the release of his new single.
> Read Digital Spy's review of 'Suit & Tie'
Listen to 'Suit & Tie' below: