Chelsea have agreed a club-record fee to sign the 21-year-old this summer as they will pay Leverkusen €80m (£72m) up front plus a further €20m (£18m) in add-ons.
According to Bild, Havertz had a medical with Chelsea in London on Sunday before he met up with Germany’s national team the following day.
Havertz is set to become Chelsea’s sixth new arrival this summer after Hakim Ziyech, Timo Werner, Ben Chilwell, Thiago Silva and Malang Sarr joined the club.
Speaking on Monday, Leverkusen boss Peter Bosz admitted that Havertz is unlikely to return to training with the German club after the international break.
When asked about Havertz’s imminent arrival at Stamford Bridge, Chelsea defender Antonio Rudiger said on Tuesday: ‘Everything went well with Timo Werner, so I made my contribution.
‘And I hope that it works again now [with Havertz].’
Havertz is currently with Germany’s national team preparing for their upcoming games against Spain and Switzerland.
The highly rated midfielder is expected to arrive at Chelsea next week ahead of their new Premier League campaign, which begins against Brighton on September 14.