New figures from Jet2.com and Jet2holidays revealed bookings to green and amber list destinations rocketed by more than 250 percent after the rules were relaxed.
The firms' chief Steve Heapy said: "It is no surprise to see a sudden spike in bookings to destinations on the green and amber lists, as we know there is enormous demand out there from holiday-makers.The extension to the Green and Amber Lists has increased customer confidence and given them the reassurance to book.
"With customers continuing to be able to plan and look forward to flights and holidays across more than 40 green and amber list destinations, this summer is a much brighter one for holidaymakers."
He added: "We hope this is just the beginning of even sunnier times ahead, as the Government continues to recognise the protection our successful vaccination programme provides when it comes to opening-up international travel."