The famous Kent links will play host in 2021, with St Andrews to stage the 150th Open a year later than planned in 2022, the R&A confirmed on Monday.
Royal Liverpool and Royal Troon will host The Open in 2023 and 2024 respectively after agreeing to push their duties back 12 months.
“We have been working closely with Royal Liverpool and Royal Troon and the relevant local agencies to reschedule the Championships,” said R&A chief executive Martin Slumbers.
“We are grateful to everyone involved at the clubs and at our partner organisations for supporting our plans and showing flexibility to adapt their own schedules. We can now look forward to seeing the world’s best players competing at these outstanding links courses in 2023 and 2024.”
The rescheduled 149th Open will be played from July 11-18 next year.
Shane Lowry, of Ireland, will be the defending champion following his victory at Royal Portrush last year, when he held off the challenge of England’s Tommy Fleetwood to win by six shots.
Royal St George’s last staged the tournament in 2011, when Darren Clarke lifted the coveted Claret Jug.
Zack Johnson was victorious when St Andrews last hosted in 2015, while Rory McIlroy took the honours at Royal Liverpool in 2014 and Henrik Stenson was the last winner at Royal Troon in 2016.
Additional reporting by PA.