If your bet is completely unmatched, then you can cancel the bet at the bet exchange and then do the bet again at the correct odds.
The most complicated scenario is when the bet has been part matched. This happens when you manage to get some of the lay bet matched and some of it unmatched (and is therefore queued).
The example below shows the following scenario:
I have backed a selection at the bookmaker for £25 at odds of 2.0. I have now layed the selection and it is partially matched. The lay odds were 2.04 when I first looked and there was enough liquidity to take my bet. Following the instructions in the calculator, I layed a stake of £25.13 at Betfair. Unfortunately the lay odds have changed to 2.1 and only £12.57 of my bet matched at odds of 2.04.
This is when most people panic as you can’t cancel the whole bet and you don’t know how much to LAY at the new price.
If this happens, cancel what is left of the original lay at 2.04. To work out how much you need to lay for the remaining part of the bet, load up the mobile friendly calculator and click 'part lays' as shown below or use the tricky bet calculator and use the part lays already in place section as shown below.
This is designed to help you figure out how to calculate partially matched bets.
Fill in the calculator:
Use the same bet type as instructed in the guide for that bet (Normal, Stake Not Returned (SNR) or Stake Returned (SR)).
Back stake is the stake you originally entered in the Calculator (£25 in our example).
Commission (5% for Betfair, 2% for Smarkets).
Or with tricky bet calculator:
So in the example above, the key points are:
- I have a total back stake of £25.
- The current odds are now 2.1. I enter this in the top section.
- The lay already in place is £12.57 at odds of 2.04. (There is room for 2 part lay if you have another part lay also)
- The amount I need to LAY now at 2.1 is £12.19.
- My overall loss for this qualifying bet with all of the LAYS matched is £1.48