Good Friday will be the busiest travel day as many people make the most of the long weekend.
Motorists are being urged to set off early or delay travel until Saturday to avoid the worst jams.
For those staying in the UK, the Met Office is predicting plenty of dry and sunny weather across the country.
Temperatures are expected to widely reach the low 20s Celsius and peak at 23C in the South.
Met Office chief meteorologist Steve Willington said: "With temperatures usually around 10-13C at this time of year, it's certainly going to be significantly warmer than average this Easter weekend and quite a contrast to the colder weather we have seen so far this month."
A survey of 1,258 people by tourist board VisitEngland indicates that 7.4 million have planned an overnight trip in the UK this weekend.
This is up from 4.8 million last year and is the most since the annual survey was launched in 2013.
Among the attractions holding special events this weekend are Blenheim Palace, Oxfordshire; Goodrich Castle, Herefordshire; Dreamland Margate, Kent and Chatsworth House, Derbyshire.
VisitEngland director Patricia Yates said: "It is great to see so many Brits are planning holidays at home in the UK in what is set to be a cracking Easter, bringing a boost for businesses and local economies as the summer season gets under way.
"Holidaying at home continues to be a great choice with the certainty of budgeting, the ease and convenience, and the quality on offer all tempting people to explore beyond their doorstep."
Travel trade association Abta expects 2.1 million British holidaymakers to head overseas this weekend, with strong demand reported for destinations including Spain, Turkey and Egypt.
Airports, ferry terminals and the Channel Tunnel will be extremely busy.
Abta chief executive Mark Tanzer said: "Easter is always one of the most popular times of year for travel and over the long weekend millions of holidaymakers will be taking either an overseas or a domestic break.
"The fact that Easter falls so late this year means that there is a good range of short-haul destinations, offering good temperatures and guaranteed sunshine.
"As always on a busy bank holiday, leave plenty of time to get to your departure port and check for engineering work and line closures if using public transport."
Research by the RAC and Inrix suggests 4.4 million car journeys for leisure trips will be made on Good Friday.
This is expected to cause many major routes to be clogged, with the worst delays between 11am and 4.30pm.
The areas most likely to see jams include:
- M62 westbound from Leeds to Manchester between Junctions 27 and 18 (56-minute delay)
- M6 northbound from Preston to Lancaster between Junctions 31 and 34
- M25 anticlockwise from Orpington between Junctions 4 and 30 (30-minute delay)
Highways England said it will remove more than 450 miles of roadworks in time for the weekend, meaning 99% of motorways and major A-roads in England will be clear of cones.
Motorists face paying the highest petrol prices for the Easter getaway in five years.
The average price of a tank of petrol has soared by more than £2.40 according to the AA.
Rail passengers also face disruption as Network Rail carries out engineering work.
London Euston, the fifth busiest station in the UK, will be closed between Good Friday and Easter Monday.
There will also be no trains at London Fenchurch Street, an amended service between Preston and Glasgow Central, and some lines closed through Wimbledon.
Network Rail said fewer passenger use trains during bank holidays compared with working days but admitted there is "never an ideal time to shut the railway for our must-do work".