More than 14 million Easter getaway trips are expected to take place with drivers being warning that journeys could take twice as long as normal.
The RAC warned of an inevitable traffic surge ahead of the bank holiday weekend, which coincides with the start of a two-week holiday for many schools.
Rail travel will also be disrupted as Network Rail carries out engineering work, with the southern section of the West Coast Main Line closed between Good Friday and Easter Monday.
With Easter falling earlier than usual at the start of the school holidays, it could be carmageddon for holidaymakers
Tourist board VisitEngland said around 11 million people in the UK are planning an overnight Easter trip, generating an estimated £3.2 billion boost to the economy.
The RAC and transport analysis company Inrix commissioned a survey which suggested 2.6 million leisure journeys by car will be made on Good Friday.
Some 2.3 million getaway trips are planned for each of Easter Saturday and Easter Sunday, with 2.0 million expected to take place on each of Thursday and Easter Monday.
A further 3.3 million Easter leisure journeys have been planned by drivers who are undecided exactly what day they will travel, leading to a total of around 14.5 million getaway trips between Thursday and Easter Monday.
Inrix predicted that the worst congestion on Thursday will be between 2pm and 7pm as people on leisure journeys compete for road space with regular commuters.
The busiest route is expected to be the western section of the M25 between the M23 for Gatwick and the M1 for Hertfordshire.
Journeys on this stretch from 4pm are expected to take over two hours, which is more than twice as long as usual.
On Good Friday, the lengthiest delays are expected to be between 11am and 3pm, meaning drivers are advised to set off as early as possible in the morning or wait until later in the afternoon.
Two popular routes for holidaymakers – the M5 southbound between Bristol and Taunton, and the M3 between the M25 and the south coast – are likely to be congested, with estimated journey times more than double what they normally are.
RAC Breakdown spokesperson Alice Simpson said: “With Easter falling earlier than usual at the start of the school holidays, it could be carmageddon for holidaymakers.
“Anyone who can delay leaving on Thursday until much later in the evening or set off as early as possible on Good Friday is likely to have a better journey than those who travel during the peak periods of the day.
“Lengthy queues can be expected along routes to the usual hotspots like the West Country, the Lake District and the south coast, especially during the middle of the day when most people make trips.”
To avoid the longest delays, we advise adjusting departure times so you’re not travelling in peak commuter hours
Inrix transportation analyst Bob Pishue said: “Although travel times will peak on Thursday and Friday afternoons, drivers should be prepared for longer journeys than normal throughout the entire weekend.
“To avoid the longest delays, we advise adjusting departure times so you’re not travelling in peak commuter hours.”
The AA advised drivers to carry out “a few simple checks” on their car before embarking on Easter journeys.
Chris Wood, AA patrol of the year, said: “Easter is the first opportunity many people have to go and see their family and we’re expecting the roads to be busy.
“Before setting off on a long journey it’s important to check your car. Take 10 minutes to check your oil, coolant and windscreen wash levels.”
Network Rail is urging train passengers to check their journey details before they travel as some major routes will be closed due to engineering work.
Tourism businesses and destinations will be looking to the critical Easter weekend for much-needed cash flow after the lean winter months so it's really encouraging to see so many of us are planning a holiday at home
The Main Line between London Euston and Milton Keynes will be shut for four days from Good Friday.
There will also be disruption in the areas around Glasgow and Huddersfield.
Network Rail’s network strategy director Laurence Bowman said: “We know how important Easter is for families and friends to catch up, and we try to keep as much of the network open as possible.
“There’s never a good time to do the work we need to do but the four days of the bank holiday, when fewer people are travelling, give us the opportunity to do major work we couldn’t do in normal weekend.
“We’ve got 493 different pieces of work taking place this Easter, most happening overnight, including laying over 8,000 metres of new rail and putting down over 40,000 tonnes of new ballast to support the tracks.”
VisitEngland chief executive Patricia Yates said: “Tourism businesses and destinations will be looking to the critical Easter weekend for much-needed cash flow after the lean winter months so it’s really encouraging to see so many of us are planning a holiday at home.
“We also know from our latest research that the cost of living remains a concern and while people are still keen to take a break, many are booking late, taking shorter breaks, wanting to save on accommodation, activities and eating out, highlighting the ongoing challenges for industry.”
– The RAC and Inrix survey of 2,136 UK adults was conducted by research company Find Out Now last week.