An unmatched bet waits at your price until someone takes it or you cancel it, and if it is still waiting at the jump, its setting cancels it, turns it into a starting price bet or keeps it. Until it is matched it is not a bet at all: it ties up the stake or liability it would need, you can cancel or change it, and only the matched part is ever settled.
The order that causes trouble is the part-matched one: a $120 back that is only $70 matched is a $70 bet, whatever the slip said when you clicked. Everything below happens before the jump, with illustrative prices.
Why bets go unmatched
An exchange matches a bet only against an offer already waiting on the other side, at your price or better. With illustrative amounts, Runner 5's ladder reads:
| Back price | Available to back | Lay price | Available to lay |
|---|---|---|---|
| $6.20 | $40 | $6.40 | $55 |
| $6.00 | $30 | $6.60 | $70 |
| $5.80 | $95 | $6.80 | $120 |
A bet stays unmatched, in whole or in part, for one of five reasons:
- You asked for a better price than anyone offers. No layer offers more than $6.20, so a back at $6.60 waits; no backer asks less than $6.40, so a lay at $6.00 waits.
- Your stake is bigger than the money at your price. Back $120 at $6.00 or better and only $70 is waiting at those prices.
- Others asked first. Offers at one price are matched in the order they arrived, so a new lay at $6.20 waits behind the $40 already there.
- The market moved away. If late money shortens Runner 5 to $5.60, a back offer waiting at $6.20 is out of line, and no layer takes it.
- The market is suspended. Nothing is placed or matched during a suspension, such as the pause around a late scratching.
How to lay a bet covers choosing a price on the lay side of a ladder like this one.
Partly matched bets and how they settle
Say you ask to back Runner 5 for $120 at $6.00 or better on the ladder above. The exchange matches you against the best prices first:
| Part of the order | Amount | Price | If Runner 5 wins, before commission |
|---|---|---|---|
| Matched | $40 | $6.20 | 40 x 5.20 = +$208 |
| Matched | $30 | $6.00 | 30 x 5.00 = +$150 |
| Waiting at $6.00 | $50 | None yet | Nothing |
Your bet is $70 at an average of (40 x 6.20 + 30 x 6.00) / 70 = 428 / 70 = about $6.11: +$358 if Runner 5 wins, -$70 if it loses. The extra 20 cents on the first $40 is price improvement, and your waiting $50 now shows on the ladder as the best offer for layers, at $6.00. A waiting offer is matched at exactly its own price.
The exchange reserves all $120 from your available balance, $70 at stake and $50 waiting. If the $50 never matches, settlement ignores it: no stake, no result, no commission. A partly matched lay reserves liability instead. Placed before that back, a lay of $50 at $6.20 sets aside 50 x 5.20 = $260, though nothing matches until the $40 queued ahead of it has been taken.
At the jump: cancel, take SP or keep
Every unmatched order carries a setting for the moment the market reaches the jump, and your exchange's terms name the default. For the $50 still waiting on the back above:
| Setting | What happens to the $50 | If Runner 5 wins | If it loses |
|---|---|---|---|
| Cancel (lapse) | Cancelled, funds released | +$358 on the $70 | -$70 |
| Take SP, starting price $5.40 | Becomes a $50 bet at $5.40 | 358 + 50 x 4.40 = +$578 | -$120 |
| Take SP, starting price $7.00 | Becomes a $50 bet at $7.00 | 358 + 50 x 6.00 = +$658 | -$120 |
| Keep | Set out in the exchange's own rules | Read them first | Read them first |
Cancel leaves you holding exactly what was matched, at prices you accepted; the cancelled part is a lapsed bet. Take SP puts the whole $120 on, but the last $50 gets a price nobody knows until the jump, and a converted lay can be sized by stake or by liability, as the take SP entry shows. Keep is the third setting, and its effect is written in your exchange's own rules. Every order here is placed and managed before the jump, so if you want an offer gone, cancel it yourself before the race starts.
Under the Interactive Gambling Act 2001, a gambling service is an in-play betting service to the extent its bets on a sporting event are placed, made, received or accepted after the event begins (s 10B). Online sports betting is lawful only when it is not in-play (s 8A(3)) and the provider holds an Australian state or territory licence (s 15AA), so online betting closes when the match starts. Cancel any sports offer you no longer want before the game begins.
Scratchings, reduction factors and unmatched lays
A late scratching changes waiting offers as well as matched bets, and each exchange's racing rules decide exactly how. These are the common rule types, so read your own exchange's version before race day:
- Bets on the scratched runner are void: matched stakes come back, liabilities are released, and its waiting offers are cancelled.
- Each runner can carry a reduction factor, an estimate of its chance of winning set under the exchange's rules. When a runner is withdrawn after bets are matched, matched bets on the others can have their prices cut by its factor, often only above a threshold the rules set.
- Waiting offers across the market can be cancelled too. Rule sets differ between exchanges, and between a race's win and place markets.
Here is why that matters for an unmatched lay. With illustrative figures, you asked to lay Runner 6 for $40 at $7.00, and $16 is matched when a runner with a 22% reduction factor is scratched.
| Part of the lay | Before the scratching | After, if the factor comes off the whole matched price |
|---|---|---|
| $16 matched | Liability 16 x 6.00 = $96.00 | Price 7.00 x 0.78 = $5.46, liability 16 x 4.46 = $71.36 |
| $24 waiting at $7.00 | Liability 24 x 6.00 = $144 if matched | Cancelled under a cancelling rule, otherwise still on offer at $7.00 |
The waiting $24 is the danger. Every runner left now has a better chance of winning, so if Runner 6's fair price has moved to about $5.46, backers will take a lay offer at $7.00 quickly. Matched there, it is worth 24 x (1 - 1 / 5.46) - 144 / 5.46 = 19.60 - 26.37 = -$6.77 on average before commission: +$24 if Runner 6 loses, -$144 if it wins. Where your exchange's rule does not cancel it, cancel it yourself as soon as a scratching is announced, then decide whether to lay again at the new price.
A fixed-odds bet at a bookmaker has no waiting part: a late scratching reaches it as the Stewards' deduction, under rules such as BR 14 of Racing NSW's Rules of Betting for NSW on-course bookmakers, which scratching deductions explains.
Risk: Betting involves risk. A scratching can change a lay's price and leave old offers in the market at prices that no longer fit the race, and there is no guarantee of profit. See responsible gambling for limits and support.
Cancelling and editing orders
You can cancel or change the unmatched part of an order whenever the market is open and nobody has taken it. Four habits keep that clean:
- Cancel, then check. A cancel and an incoming match can cross, and whatever matched before your cancel arrived stays matched, so read the matched amount after every cancel.
- Expect an edit to cost your place. Check whether your exchange keeps your place in the queue when you change the price or stake; where an edit counts as a new offer, it joins the back of the queue at its new price.
- Offset a matched bet rather than trying to cancel it. To reduce a matched bet, place an opposite bet at the current price: a new bet at its own price, netted with the first for commission.
- Clear the list before the jump. Cancel every offer you no longer want, then check that your unmatched bets list is empty, or holds only what you meant to leave there.
Unmatched bet mistakes, with what each costs
With illustrative prices and an illustrative 6% commission:
| Mistake | What it costs |
|---|---|
| Treating a placed hedge as a matched one | You back Runner 8 with Bookmaker A for $20 at $7.30 and ask to lay $25 at $5.90, which, matched in full, would leave +$3.50 either way. Only $10 is matched by the jump and the rest lapses: +$77.00 if Runner 8 wins, -$10.60 if it loses |
| Leaving a lay offer up through a scratching | The $24 lay at $7.00 above, matched after the factor cut Runner 6's price, is worth -$6.77 on average |
| Choosing take SP for a lay without checking how it is sized | Sized by stake, a $24 lay left unmatched at $7.00 and converted at a $9.00 starting price risks 24 x 8.00 = $192, not the 24 x 6.00 = $144 you planned; sized by liability, it keeps the $144 risk but its stake falls to 144 / 8.00 = $18, so it wins $18, not $24, if Runner 6 loses |
The working for the first row: lay stake = 20 x 7.30 / (5.90 - 0.06) = 146 / 5.84 = $25.00, with a liability of 25 x 4.90 = $122.50. A full match leaves 126 - 122.50 = +$3.50 if Runner 8 wins and 25 x 0.94 - 20 = +$3.50 if it loses. With $10 matched: 126 - 10 x 4.90 = +$77.00 and 10 x 0.94 - 20 = -$10.60.
Where B337 fits
Because B337 never backs or lays on the exchange, every order, setting, cancel and edit here happens in your own exchange account. The Terminal shows Betfair back and lay beside racing and sports prices from 40+ bookmakers, with flucs and a countdown to the jump on each race, so you can see where the exchange price sits against bookmakers before you choose your own.
Its prices are collected on a repeating cycle and can trail the exchange's own, so check what is matched and unmatched in your exchange account, not on the board. A free account opens a limited view of the Terminal with live odds, which does not include Betfair's prices. Bookmaker names are trade marks of their owners. B337 is not affiliated with them. Liability and commission are covered in the lay betting hub.
Risk: Betting involves risk. Only the matched part of an order is a bet, an unmatched hedge leaves the original bet open at full size, and there is no guarantee of profit. See responsible gambling for limits and support.