An All-In bet is a wager where your odds stay fixed regardless of any scratchings. However, if your selection doesn’t run or compete in the event, you lose your stake - no refund applies.
If your selection does take part, the odds you locked in are often higher than the final Fixed-Odds price, giving you potential extra value. This highlights the risk versus reward nature of All-In betting: you accept the risk of no refund for the chance at better odds.
To identify an All-In market, click the 'i' icon and read the details; an icon will always be present for All-In markets.