Fundraising efforts have been under way for several weeks, but the main show kicks off on Friday night
Sport Relief is hoping to beat the £50.4m it raised on its TV show two years ago in a star-studded night of performances and sketches on Friday.Gary Lineker and Davina McCall are among the hosts on a show which aims to raise money for poor and disadvantaged people in the UK and around the world.
Sketches will include David Beckham joining Only Fools and Horses.
DJ Jo Whiley completed a 26-hour stint on a treadmill on Thursday, earning a £260,000 donation from Coldplay.
A tweet from the band read: "Massive respect to the incredible, indegafatible @jowhiley #10K per hour makes #260K sponsorship from us."
Speaking afterwards, the Radio 2 DJ said: "I am blown away by Coldplay's generosity and it has made this challenge all the more sweeter."
At the climax of the gruelling 26 hours, Whiley stumbled following a final 10-second countdown. "I can't believe I did 26 hours and then fell at the last minute," she added.
Highlights of this year's Sport Relief are set to include the following:
- Singer Cheryl Cole will introduce a special film raising awareness about malaria.
- Del Boy and Rodney will be back on TV screens after 10 years with a one-off Only Fools and Horses sketch, featuring one of the show's biggest fans - David Beckham.
- David Walliams will oust John Humphrys as Mastermind host, with contestants including England and Arsenal player Jack Wilshere.
- Four Paralympians will swap their sports kit for sequins for a Sport Relief Does Strictly special.
- The premiere of the official England 2014 World Cup song, a cover of Take That's Greatest Day, will take place.
- Wimbledon champion Andy Murray will take part in a Mock The Week special.
- Little Mix will perform the Sport Relief single, Word Up, with further musical performances from Kylie Minogue and Boyzone.
She contracted the disease on holiday four years ago, not long after climbing Mount Kilimanjaro for Comic Relief.
Having received the treatment she needed to make a full recovery, the singer will introduce a special film, shot in a hospital in eastern Uganda.
"When I climbed Kilimanjaro for Comic Relief five years ago it was honestly one of the hardest things I've ever done," the singer said.
"The motivation lay in knowing it could help in eradicating malaria and ultimately saving lives by providing mosquito nets.
"I didn't for one minute think that only a year later I would get malaria myself and become so ill that at one point I was given 24 hours to live.
"I was lucky, I had the best care I could get. Some people are not so lucky. A £5 mosquito net could keep a child safe and really does help."
Fundraising efforts have been underway for several weeks.
Davina McCall raised more than £750,000 by running, cycling and swimming from Edinburgh to London in just seven days.
DJs from BBC Radio have also completed gruelling endurance tests inside a perspex box in front of BBC Broadcasting House, in London.
On Monday, Radio 1 host Nick Grimshaw completed a 12-hour bike ride after he, along with other celebrities, cycled more than 1,000 miles and raised more than £115,000.
Elsewhere, former England captain Alan Shearer beat ex-footballer Robbie Savage in an exhausting race to sit on all 90,000 seats in Wembley Stadium.
The fundraising telethon starts on BBC One at 19:00 GMT.
LWDLIK - It's going to be a great night hope we, in Kuwait, can make a fine contribution.