Back to lay is a trading method where you back a selection on a betting exchange and later lay it at shorter odds. If the price falls, you can lock in a small profit whatever happens. If it lengthens instead, you decide whether to close at the new price or keep the bet running.
The maths is straightforward. The hard part is knowing which way the price will go, and the data below shows how prices actually behaved over a year.
Read the transcript
Back to lay means backing a price, then laying it back once it shortens, so you lock in a profit before the event ends.
Say you back twenty pounds at two point four. If it shortens to two point two, you lay twenty-one eighty-two for a one pound eighty-two profit. At two point one, you lay twenty-two eighty-six and lock in two eighty-six.
Prices move on team news, on money arriving, and once the match is in-play, on goals and red cards. You need a good reason to expect the price to move your way.
Timing matters too. Days before kick-off, the exchange match odds book carried a margin of around two point eight per cent, against under one per cent at kick-off. Prices get sharper the closer you get to the start.
Back to lay is all about reading which way the price will move. Have a reason, have an exit, and please bet responsibly.
Key points
- You back first at a bigger price, then lay the same selection at a smaller one.
- Lay stake = back stake × back odds ÷ lay odds, which spreads the result evenly across every outcome.
- If the price lengthens instead, the trade misses its target, so set your exit prices in advance.
- The outcome depends on reading the price move better than the market does.
What back to lay is
On a betting exchange you can back an outcome, betting on it to happen, or lay it, betting against it and taking the bookmaker’s role. A back to lay trade uses both: you back at one price and later lay the same selection at a shorter one.
Because the lay goes on at lower odds than the back, the two bets together leave a small result however the match ends. Some people try it before kick-off, for instance when they expect team news to shorten a price, while others try it in-play during a spell of pressure. If exchanges are new to you, our Betfair Exchange (Lesson 8 out of 25 in the Masterclass) guide explains back and lay prices first.
Step by step
- Choose a selection and note the back price. Check how much money is waiting at each price too, because quiet markets jump around.
- Back it at your chosen stake, and decide in advance both the price you hope to lay at and the price at which you will close if it lengthens.
- Wait for the price to move. It needs to shorten for the trade to finish ahead.
- Lay the same selection, with a lay stake of back stake × back odds ÷ lay odds, so the result is the same on every outcome.
- Check the result after commission, which the exchange charges on net winnings in each market.
Most exchanges have a cash out or green up button that handles step 4 for you. Our page on how to green up a trade shows the sum in more detail.
Worked example
Worked example
Before kick-off you back Tottenham for £25 at 3.10 away at Everton (prices for illustration only). Later the price shortens to 2.85, so you lay it.
- Lay stake: 25 × 3.10 ÷ 2.85 = £27.19.
- If Tottenham win: the back bet pays 25 × 2.10 = £52.50 profit and the lay costs 27.19 × 1.85 = £50.31 from your liability. Net +£2.19.
- If Tottenham don’t win: the back bet returns nothing and the lay pays £27.19. Net +£2.19.
Quick check: 25 × (3.10 ÷ 2.85 − 1) = £2.19 before commission. At 2%, used purely as an example rate, commission costs about 4p, leaving roughly £2.15.
That result is small next to the £25 stake, which is normal, because a move from 3.10 to 2.85 is fairly modest. In chance terms, 3.10 is about 32.3% and 2.85 about 35.1%. The odds converter below turns any price into a chance.
Odds converter
Liability, suspensions and timing
When you lay, your liability is what you would pay out if the selection wins, equal to lay stake × (lay odds − 1). In the example that is 27.19 × 1.85 = £50.31, which the £52.50 from the back bet covers.
Prices lengthen as well as shorten, so when you exit matters. If you never close, you are simply holding an ordinary £25 bet until full time. In-play markets also suspend when a goal or red card happens, so the price after the restart can be a long way from where you planned to exit.
What the data says
We compared Betfair Exchange prices several days before kick-off with prices at kick-off across more than 6,500 matches in 20 European leagues between 20 October 2025 and 19 October 2026, using data from football-data.co.uk. The test was simple: back every selection early, then lay it at the kick-off price.
- Prices lengthened more often than they shortened.
- Commission made only a tiny difference to the average result, about 0.04 percentage points.
- Early books carried more margin: the match odds market had a 2.8% margin early, against 0.9% at kick-off.
In other words, early prices tended to carry more margin and to lengthen before kick-off. These are averages across many matches, so they describe the market rather than a method to follow.
The honest limits
The trade itself creates no value. Backing at 3.10 just takes a price, and the later lay only locks in what the market did next. A back to lay trade is only as good as your reason for expecting the price to fall.
That reason has to be something the market hasn’t priced yet, such as sharper judgement or better information. One honest test is closing line value (Lesson 9 out of 25 in the Masterclass): if your back prices are usually worse than the kick-off price, the trade will struggle whatever exit you choose.
Keep stakes small and fixed and set your exit prices before you start. Our bankroll management (Lesson 11 out of 25 in the Masterclass) guide covers stake sizing, and betting variance (Lesson 13 out of 25 in the Masterclass) explains why results swing from week to week. Never raise your stake to make up for an earlier trade.
Related guides
- Football trading explained
- How to green up
- Betfair Exchange prices (Lesson 8 out of 25 in the Masterclass)
- Closing line value
- Lay the draw
18+ only. Betting should stay fun. Set a budget before you start, only bet what you can comfortably afford, and take a break whenever you need one. For free, confidential support, visit BeGambleAware.org or call the National Gambling Helpline on 0808 8020 133.