As many as 2.1 million people are due to travel abroad this bank holiday weekend, Abta estimates.
Holidaymakers are being urged to leave plenty of time to travel to their point of departure.
Airports around the country are expecting to be very busy over the August bank holiday weekend, with Heathrow reporting that 243,000 people will fly out on Friday alone.
Gatwick is expecting 304,000 holidaymakers to fly out over the entire weekend and 174,000 people will be departing from Stansted.
Bristol airport is expecting 55,000 holidaymakers to fly out, 90,000 will depart from Edinburgh, 95,000 from Birmingham, 36,000 from East Midlands and 210,000 from Manchester.
Ports and the Channel Tunnel are also expected to be busy over the weekend.
Eurostar is anticipating more than 64,000 departures from the UK across the four days, as Paris and the South of France remain firm favourites with British holidaymakers.
With temperatures around the Mediterranean expected to hit the low 30 degrees over the weekend, Spain remains a popular destination, according to Abta.
Southern Spain, the Balearics and the Canary Islands in particular are all expecting large numbers of British holidaymakers.
Abta embers are reporting that Turkey and Greece are also very popular, with Crete expected to be a top choice. Further afield, Florida and Morocco have also sold well.
Dublin, Amsterdam and Paris are the top short-haul getaway destinations together with with long-haul city breaks to New York and Los Angeles.
The Norfolk Broads, the West Country and the Cotswolds are top picks for domestic breaks.
Abta chief executive Mark Tanzer said: “This weekend is always one of the busiest of the year for travel, and marks the final week of the peak summer season.
“Hundreds of thousands of people take advantage of the extra day off work to head overseas for some guaranteed sunshine, or to enjoy the UK’s beautiful countryside and vibrant cities.
“With roads and airports expected to be extremely busy this weekend, I would remind holidaymakers to make sure they leave plenty of time to get to their port of departure.”
Almost 70,000 passengers are expected to pass through Liverpool John Lennon airport over the long weekend – an increase of 5% year-on-year and the busiest August bank holiday period since 2011.
A spokesman said: “August bank holiday weekend is always our busiest time and this year with many people so fed up of the miserable summer weather here at home, we expect even more passengers will take advantage of flying from Liverpool to a host of destinations a lot warmer than here in the UK.”