Shares in online trading firm IG Group yesterday suffered their biggest one-day fall for a decade after a surprise slump in revenues.

The FTSE 100 company, the world’s first spread-betting firm, said sales in the third quarter were down 14 per cent on a year earlier at £240million.

The London-based company said it now expects full-year revenues to grow in the ‘mid-single-digit’ percentage range, having previously targeted a 10 per cent to 15 per cent expansion.

IG shares fell 27 per cent in early trading – the biggest fall since 2016 – before closing down 23 per cent at 990p.

The shares are now at their lowest level since April last year.

The rout was echoed across the industry, with Plus 500 down 14 per cent at one stage and CMC Markets down as much as 9 per cent.

IG boss Breon Corcoran blamed ‘less supportive market conditions’ in the third quarter. 

This came despite ongoing turmoil on financial markets amid rising bond yields and a volatile oil price – factors that typically boost platforms such as IG as customers ramp up trading activity.

But a revamped hedging strategy meant revenue retention at its ‘over-the-counter’ (OTC) division – the share of OTC trading flows it keeps – slipped from about 80 per cent to around 70 per cent.

It was the second time in recent months that IG has spooked investors, having suffered a sharp fall in its share price at the end of July – when disappointing half-year results coincided with the near-£1billion acquisition of US prediction markets business Underdog.

Corcoran, who took charge in 2024 and guided the company into the FTSE 100 in March this year, said: ‘Growth in first trades and active customers remained strong.

‘Lower revenue reflected reduced OTC revenue retention in less supportive market conditions.’

Set up by millionaire Brexit supporter Stuart Wheeler in 1974, IG started life as Investors Gold Index and allowed punters to speculate on gold without buying physical bullion as it was then restricted by UK exchange controls.

It grew to become one of the country’s largest trading groups and joined the London stock market in 2000 – becoming the first spread-betting company to do so – having expanded from gold into other areas including sports betting and foreign exchange.