You will see on the calculator that there is an option to change the calculations so that your bet is underlaid or overlaid. When you perform a normal matched bet, the calculation is normally totally balanced, so you get the same return or loss regardless of whether your back bet wins or loses. Underlay and overlay changes this so that your bet is skewed to increase the return of one outcome over another.

What is Underlay?

When you underlay, you are laying less than you normally would. The result of this, in a matched betting scenario is that you wouldn’t make as much if the matched bet wins at the exchange but win more if the bet wins at the bookmaker. There are a number of scenarios where this can be useful:

Smaller Free Bets That You Think Will Win

Underlaying on smaller free bets can be a great way of maximising your returns on events that you are confident will win. By underlaying you will win a greater amount if the event wins at the bookmaker, but won’t win anything if it loses (wins at the exchange). However you won’t lose anything either,so you essentially get a risk free bet on an event that you think will win. This can add some excitement to an event if you are watching it, without the risk too, just be aware that you may come out with nothing if things don’t go your way.

With larger free bets, we would still recommending matching it using the traditional method, so that you guarantee a return regardless of the outcome.

Bonuses With High Wagering Requirements

If bonuses have high wagering requirements before you can withdraw, it can be worth underlaying. If underlaying you want to place the entire balance in one bet if you can. If the bet loses, you are done with the offer, albeit with less than if you did a normal matched bet. If it wins however, you have a greater amount of money in your bookmaker account making it more worth your time to complete the wagering requirements.


What is Overlay?

Overlaying is exactly the opposite to underlaying. You are laying more than is required to evenly match the bet. This can be expensive and your liability can add up quickly on higher odds events. This can be useful in the following circumstances

Get a Free Bet If You Pick A Winner

This would be the bet365 pick a 4/1 winner or Betfair Sportsbook 3/1 winner and get a free bet. If you overlay the qualifying bet, you will get more back than your initial stake. But if the bet wins at the bookmaker you will need to payout more in liability, but this is offset by the free bet that you will receive for picking a winner. It is worth noting that your liability can’t be increased by more than the free bet amount, as you would end up out of pocket. So overlaying represents a better opportunity the lower the odds are. This should be caveated by the fact that the lower the odds are, the greater the chance of winning and thus reducing the value of the free bet.