As many as 18.4million could be expected to get into their cars this Bank Holiday Monday as they make their way home, the AA said.
Congestion is set to return to pre-pandemic levels, according to the British motoring association.
Large festivals taking place over the weekend, including Reading Festival, combined with the forever changing restrictions of overseas travel would create “the perfect storm” for congestion, the AA told PA news agency.
The warning comes as travellers on Friday faced gridlock when they tried to get away for the Bank Holiday weekend.
Just days ago, it was revealed the great staycation was more expensive than travelling abroad.
Accommodation at the Italian beauty spot cost £631 for two people, while in Lake Windermere it was £2,381, according to consumer group Which?.
Which? travel editor Rory Boland told The Times: “Holidaying at home has always been expensive but the situation has become far worse during the pandemic and it’s no wonder many people have felt priced out of a holiday this year.
“The reasons for these higher prices are complex, but it is hard to avoid the conclusion that some unscrupulous accommodation providers are charging over the odds.”