Our picks in detail
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1. Smarkets: best overall
8.7/10 Smarkets is run by Smarkets (Malta) Limited, licensed by the Gambling Commission as a betting exchange since November 2014, with no regulatory action on the register since it began in November 2023. It charges 2% commission on your net winnings per market; only very active traders (a 1% Pro tier) and its most profitable customers (a 3% Select tier) pay other rates. Deposits and withdrawals are free, from £10 by open banking, debit card, Apple Pay, Google Pay or Trustly, or £25 by PayPal, and withdrawals are processed within 6 hours. Its politics markets are branded Smarkets Predictions. The iOS app is rated 4.77; the Android app only 2.8.
Full Smarkets review Smarkets alternatives
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2. Betfair Exchange: biggest exchange
8.6/10 Betfair Exchange is run by TSE Malta LP, licensed by the Gambling Commission as a betting exchange since November 2014. It's the biggest exchange in the UK by app ratings, 4.72 from 30,330 on iOS, and covers Premier League and international football, racing's biggest festivals, tennis, cricket, golf, rugby and election results, with back and lay bets, your own odds and MatchMe. Your commission depends on your My Betfair Rewards package; Betfair's example gives 2% for the Basic package. Accounts with more than £25,000 of gross profit over 52 active weeks can pay an Expert Fee. In December 2025 its licensee was part of a £2 million settlement over customer-interaction failings.
Full Betfair Exchange review Betfair Exchange alternatives
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3. Matchbook: prediction-style markets
7.6/10 Matchbook is run by Triplebet Limited, registered in Alderney and licensed by the Gambling Commission as a betting exchange since November 2014, with no regulatory action on the register since it began in November 2023. Its exchange offers back and lay bets, bet builders, multiples, in-play betting and, according to its app listing, live streams of every horse race and greyhound race. Matchbook Predictions, run with ADI Predict Street, adds yes/no markets priced as percentages, from football to general elections. In October 2026 Triplebet agreed to buy the Betdaq brand. Its commission rates, payment methods and support hours weren't readable from outside the UK.
Full Matchbook review Matchbook alternatives
How betting exchanges work
On a betting exchange you bet against other people, not a bookmaker. You can back an outcome, betting that it happens, or lay it, betting that it doesn’t, by taking the other side of someone else’s back bet. Users set the odds, the exchange takes no side, and instead of building a margin into its prices it charges a commission on your net winnings in each market; you pay nothing on a market where you make a net loss.
Laying means you can lose more than you stand to win. Lay £10 at odds of 5.0 and you win £10, less commission, if the outcome doesn’t happen, but lose £40 if it does: that £40 is your liability.
Prediction markets such as Polymarket work the same way, with yes/no contracts priced as probabilities: a price of 60¢ is odds of about 1.67. Some UK exchanges now present their markets like that. Smarkets brands its politics page Smarkets Predictions, and Matchbook Predictions prices every outcome as a percentage. The Gambling Commission licenses exchanges as betting intermediaries, and nine companies held that licence on its register of October 22, 2026.
How the three compare
All three have held their exchange licence since November 1, 2014. Betdaq, a fourth exchange, closed on October 21, 2026, after Matchbook’s operator agreed to buy its brand, so we don’t rank it.
How we scored them
We couldn’t get matched-volume figures that compare the exchanges, so we judge liquidity by the size of each exchange’s user base, using app ratings as a guide. Betfair’s and Matchbook’s sites were blocked to us from outside the UK, so we used their app listings, developer pages and Internet Archive copies, and scored what we couldn’t check conservatively. We haven’t yet reviewed the five other companies with an exchange licence, and we don’t list or score bonuses. The full method is in how we rank betting exchanges in the UK.
What it costs
On an exchange, the commission is the price. At 2%, a winning £100 back bet at 3.0 makes £196 instead of £200, which works like odds of 2.96. So an exchange price only beats a bookmaker’s if it’s still higher after commission: backing £100 at 2.10 on an exchange charging 2% wins £107.80, £2.80 more than a bookmaker’s 2.05, but you’d need more than 2.07 just to match it.
Very active and very profitable customers pay differently. At Smarkets, traders placing more than 1,500 bets or staking more than £1m a month must opt in to a 1% tier, and customers above £25,000 of net profit over 12 months pay a 3% tier, both charged on every settled bet. Betfair’s Expert Fee tops up the fees of accounts with more than £25,000 of gross profit over 52 active weeks to 20% of their gross profit, or 40% above £100,000. Our commission calculator works out any back or lay bet and compares it with a bookmaker’s odds.
Polymarket, Kalshi and other prediction markets
- Polymarket lists the United Kingdom among the places where users can close existing positions but can’t open new ones, and holds no Gambling Commission licence. See is Polymarket legal in the UK?
- Kalshi lists the United Kingdom among the restricted jurisdictions from which its members may not trade.
- IG: the register shows a pending application for a general betting licence from IG View Limited, with “ig prediction markets” among its trading names.
- Event contracts sold as financial products fall under the Financial Conduct Authority’s ban on selling binary options to retail customers, in force since April 2, 2019.
Our guide to whether prediction markets are legal in the UK explains the rules.
Staying safe
- Check the register. Only operators licensed by the Gambling Commission may take bets from people in Great Britain, at the addresses on its register. Our licence check searches it, exchanges included.
- Know your liability. When you lay, you can lose several times what you stand to win: laying at 5.0 risks £4 for every £1.
- Never bet on inside information. It can be cheating under section 42 of the Gambling Act, and people accused of betting on the date of the 2024 general election with inside knowledge are being prosecuted.
- Stay with licensed sites. Unlicensed platforms aren’t part of GAMSTOP, and if one won’t pay, there’s no British regulator to complain to.
Taxes
Bettors pay no tax on winnings in the UK, exchange winnings included: HMRC’s position is that betting and gambling “do not constitute trading”. See gambling taxes in the UK.
Betting responsibly
On an exchange, every winning market pays commission, so bettors as a whole lose over time. Set a deposit limit before your first bet, never chase losses, and stop when it isn’t fun. The National Gambling Helpline on 0808 8020 133 is free, confidential and open 24/7, and GAMSTOP blocks you from every licensed site at once; our guide to gambling help in the UK explains both.