More than £1 billion will have been raised for charity following this year's London Marathon ©London Marathon

Total money raised for charity at the London Marathon is set to surpass the £1 billion ($1.3 billion/€1.1 billion) mark at this year's race on Sunday (April 28).

The landmark milestone will mark an historic moment for an event launched in 1981. 

"The London Marathon has set a world record for fundraising for an annual one-day event every year since 2007, with an incredible £63.7 million ($82.5 million/€73.6 million) raised from the 2018 event," London Marathon race director Hugh Brasher said. 

"That brought the total raised since 1981 to more than £955 million ($1.2 billion/€1.1 billion) and on Sunday, in the 39th London Marathon, we will break the £1 billion mark.

"This is a phenomenal achievement and part of what makes the London Marathon unique.

"No other mass participation event comes anywhere near this kind of fundraising."

It is estimated that 75 per cent of the 40,000 runners who take part in the London Marathon raise money for charity ©Getty Images
It is estimated that 75 per cent of the 40,000 runners who take part in the London Marathon raise money for charity ©Getty Images

Half of the money has been raised in the past nine years with the amount pledged to charity in this year's race expected to be up by 20 per cent on 2018. 

Donations through Virgin Money Giving are already up by a fifth on 2018, when £24.8 million ($32.1 million/€28.7 million) was raised, contributing to the overall event total of £63.7 million – a world record for an annual single-day fundraiser for a 12th successive year.

It is estimated that 75 per cent of the field of 40,000 runners run in the London Marathon for charity. 

The average raised per runner last year through the Virgin platform was £2,100 ($2,700/€2,400), and organisers expect that to rise significantly for this year's event. 

This year's official charity of the London Marathon is the Alzheimer's Society.