UK bookmakers are reporting mixed results from yesterday's EU referendum, while industry insiders have estimated the surprise Brexit vote will have cost betting companies more than £5m.
Online gambling group Betway said it had been left in a "political betting bloodbath" following the Leave result.
Just after polls closed last night Betway was taking Brexit bets at 12/1 odds, but just a few hours later the result was feeding through and losses began to stack up. The company has now said it is sure this is its biggest ever loss on a non-sport book.
Betway spokesman Alan Alger said: "Britain voting to leave the EU is the worst non-sporting result Betway has ever had – a true political betting bloodbath. We’ve lost almost a third of turnover on this market, with pro-Brexit punters taking advantage of extremely generous prices.
"Just like the general election, the polls got it wrong again and punters beat the bookies by sticking with their instincts."
Alger added that the Leave vote is likely to cost the bookmaking industry at least £5m, while industry insiders estimate £15m was bet across all groups in total.
Read more: Brexit slashes bookmakers' share prices
Meanwhile, betting exchange Betfair said the EU referendum market reached a record £127m of traded volume, while more than £85m was traded on polling day.
Naomi Totten, spokeswoman for Betfair, said:
The EU referendum market drew a remarkable amount of interest, most notably on the day of the vote itself, trading over £85m. In normal circumstances when a market is showing this much confidence in a result, the probability dictates that it will happen. But this referendum market was as extraordinary as the result itself and Betfair punters were left stunned by the market reaction.
At one point after the Sunderland result had been announced, there was more than £5-10k being traded per second on the market, which is absolutely huge. In contrast, Cheltenham Festival races trade around £2k per second.
Mixed results for major bookies
Combined retail and online bookmakers William Hill and Ladbrokes reported mixed results. A William Hill spokesman told City A.M. it had made a six-figure loss, while it took around £2.5m in total betting on the referendum campaign.
When voting closed, the odds were strong for Remain, but by around midnight they began to move very close together and Leave then became the favourite, in the biggest single turnaround in a day or night session for a political betting event.
In contrast, Ladbrokes said it had made a profit on the referendum
"We made a small profit on the referendum in the end," a Ladbrokes spokesperson told City A.M. "Generally, bookmakers win money when a favourite loses and lose money when a favourite wins.
"There was record interest in this and the most encouraging thing for us is the sheer level of engagement in a non-sporting event. The British public took to political betting in a big way which is very encouraging."
In a statement released this morning, Ladbrokes said betting markets will face "tough questions" on why they got the Brexit outcome wrong, after odds yesterday put Remain in a huge lead.