A bonus bet can be converted with no exchange account, and the honest answer is that every way of doing it is worse than laying the bet. There are three routes: back the other side at a second bookmaker, take the bonus bet unhedged, or open an exchange account and lay it. The third is the benchmark, and the other two are measured against it.
This page prices all three on the same illustrative $50 stake-not-returned bonus bet, with every figure computed from the prices shown. The short version is that the second-bookmaker route does work, costs roughly five times what the exchange route costs, and only exists at all on a market with exactly two outcomes.
Why the exchange is the benchmark
A lay bet is the same bet taken from the other side, in the same market, against the same set of prices. That matters for two reasons.
The first is price. When you lay, the only margin you pay is the commission the exchange charges on a winning market, plus whatever gap sits between the back price and the lay price. When you back the other outcome at a bookmaker instead, you pay that bookmaker's margin on top of the first one. The two costs are also charged on different amounts: commission comes out of the lay's winnings, while the pair of bookmakers' margin is paid on the whole return the hedge has to replace. The arithmetic below puts both in dollars.
The second is coverage. An exchange prices one runner or one selection at a time, so a lay exists on markets where there is no single opposite side to back, which is most racing markets and every market with more than two outcomes.
Commission rates are set by the exchange and vary by market and by account, so the 5% used below is an input to the arithmetic, not a stated fact. Betting exchanges covers how the back and lay sides and commission fit together, and hedging bets runs the same two routes on an ordinary cash bet. This page is only about a bonus bet, where the stake is not yours to get back.
The bonus bet being priced
Stake not returned means the stake does not come back with a winning bet: only the winnings are paid. So a $50 bonus bet at $4.00 pays 50 x (4.00 - 1) = $150 if the selection wins, and nothing if it loses. See stake not returned for the variants.
Example: Illustrative prices, chosen to show the arithmetic. Not a real event and not a current offer. The market has exactly two outcomes, A and B.
- The bookmaker holding the bonus bet prices A at $4.00.
- The best price on B anywhere else is $1.25.
- The exchange shows A available to lay at $4.10, with commission treated as 5%.
The two bookmaker prices add to 1 / 4.00 + 1 / 1.25 = 0.25 + 0.80 = 1.05, so the pair of books is a 105.0% market. That 5.0% is the margin the no-exchange route pays for a fixed result, and because it is charged on the whole $150.00 return it costs 150 x 0.05 = $7.50 against a pair of books that added to 100.0%.
Option one: the other side at a second bookmaker
Back B with cash, sized so both outcomes pay the same. The stake is the bonus bet's winnings divided by the other price: 150 / 1.25 = $120.00.
| If this happens | The bonus bet pays | The cash bet pays | Net |
|---|---|---|---|
| A wins | $150.00 | minus $120.00 | $30.00 |
| B wins | nothing | 120.00 x 1.25 = $150.00, a $30.00 profit | $30.00 |
So $30.00 either way, which is 60.0% of the bonus bet's face value. Note what it does not save: you still have to put $120.00 of your own cash at the second bookmaker, which is about the same money an exchange liability would tie up.
Where it works is narrow. The market needs exactly two outcomes and no third result, so a head to head in a sport that cannot be drawn, a two-way total, or a line that cannot land exactly on the number. A market with three outcomes means covering two of them with two cash bets, at a combined book worse than 105.0%, and the sum of three bookmaker prices is where this route stops paying.
Option two: take the bonus bet unhedged
This is not conversion at all. The bet pays $150.00 or nothing, and the only way to price it is on average.
Using the exchange's lay price of $4.10 as the estimate of A's chance, that chance is 1 / 4.10 = 24.4%, so the average value is 150 / 4.10 = $36.59.
That is the highest of the three numbers on this page, and it should be. Nothing has been given up to a spread, a commission or a second bookmaker's margin. What it buys instead is a result of nothing on 75.6% of selections, and an average worked over fifty bonus bets says nothing about this one.
Note: A stake-not-returned bonus bet is worth more at a longer price, because only the winnings are paid. The ceiling on any hedge is (back price - 1) / back price: 50.0% at $2.00, 75.0% at $4.00 and 90.9% at $11.00, before the cost of hedging. That is the reason these bets tend to go on at longer prices.
Option three: lay it at the exchange
The formula, with commission as a decimal:
- lay stake = bonus bet x (back odds - 1) / (lay odds - commission rate)
- liability = lay stake x (lay odds - 1)
- kept either way = lay stake x (1 - commission rate)
On the prices above, the lay stake is 50 x (4.00 - 1) / (4.10 - 0.05) = 150 / 4.05 = $37.04. The liability is 37.04 x 3.10 = $114.81, and the cash kept either way is 37.04 x 0.95 = $35.19, which is 70.4% of the $50.00 face value.
That assumes the lay is matched in full at $4.10. An unmatched or part-matched lay leaves that part of the bet unhedged, which is the one way this route turns back into option two. The free bonus bet converter works the lay stake, the liability and the cash kept, and how to lay a bet covers the mechanics.
The three routes side by side
One $50 stake-not-returned bonus bet at $4.00, three ways. Illustrative prices, every figure computed above.
| Route | Cash or liability | If A wins | If A loses | Kept | Share of the $50 |
|---|---|---|---|---|---|
| Second bookmaker, B at $1.25 | $120.00 cash | $30.00 | $30.00 | $30.00 every time | 60.0% |
| Exchange lay at $4.10, 5% commission | $114.81 liability | $35.19 | $35.19 | $35.19 every time | 70.4% |
| Unhedged | nothing | $150.00 | nothing | $36.59 on average | 73.2% on average |
Read the last column against the unhedged average, because that is the cost of a fixed result. The exchange route gives up $1.40 of the $36.59, which is 3.8%. The second-bookmaker route gives up $6.59, which is 18.0%, or about 4.7 times as much for the same job.
Risk: Betting involves risk. Bookmakers can restrict or close accounts and void bets, automation can fail, prices move, and a positive expected value bet can still lose. Promotions carry each bookmaker's own terms, and a bonus bet that loses pays nothing. There is no guarantee of profit. See responsible gambling for limits and support. Every number here assumes both legs are accepted and settled at the prices shown, and a hedge with one leg missing is simply a bet.
Note: To match the exchange route's $35.19, the second bookmaker would have to price B at about $1.31, putting the pair of books at 101.3% rather than 105.0%. At $1.30 the route keeps $34.62, still $0.57 short.
Two bookmakers, two sets of terms
The exchange route has one bookmaker leg. The no-exchange route has two, and that is a second risk rather than the same risk twice.
Settlement is the first half of it. Each operator applies its own rules to a void bet, a palpable error, a late withdrawal, an abandoned event and a dead heat, and those rules are not identical between books. If one leg is voided and the other stands, the position stops being a hedge at the moment it matters. Check how both operators settle the specific market before the second leg goes on, not after.
The accounts are the second half. Two accounts now carry offer-driven activity instead of one. Bookmaker terms govern what may be done with a promotion, many restrict automated betting and third-party access, and a bookmaker can limit stakes, void bets or close an account at its own discretion. No software prevents that, and B337 makes no claim that it avoids it. Whether any of this is lawful where you are is a question for your own legal advice: B337 does not give legal advice, and bookmaker terms are a separate matter from the law.
There is also cash to move. The $120.00 has to be deposited at the second bookmaker and later withdrawn, and a balance spread over several books is harder to keep track of than one exchange balance.
Racing barely has an opposite side
A win market has no opposite side to back. Covering a bonus bet on one runner means backing every other runner, and the price of the rest of the field decides whether that is worth doing.
Take the same $50.00 bonus bet at $4.00 in an eight-runner race, where the other seven runners' prices imply chances adding to 0.90, so the whole book is 0.25 + 0.90 = 115.0%. To return the same $150.00 whichever of them wins, the cash stakes have to total 150 x 0.90 = $135.00, which leaves 150 - 135 = $15.00 either way. That is 30.0% of the bonus bet, against 70.4% for the exchange lay on the identical bet.
One late scratching re-prices the whole thing, and a deduction applied to a fixed-price bet moves the leg already placed. This is why the no-exchange route is mostly a sports answer, and why racing promotions are normally valued against the exchange instead: money back racing promos shows that valuation, and how to value a betting promotion covers the general method.
Where B337 fits
The Terminal is B337's live odds board: it collects the prices bookmakers publish and Betfair's own exchange prices and lines them up, so racing and sports prices from 40+ bookmakers sit side by side with Betfair back and lay. B337 uses Betfair as the price reference, so both numbers the arithmetic above needs sit on one screen. Prices are read on a repeating cycle, not tick by tick, so check both in your own accounts before either leg goes on. A free account opens a limited view of the Terminal with live odds, and the Betfair columns start at Terminal View.
On racing, the Classic Racing strategy can optionally lay a bet it has just placed on the same runner on Betfair, in an exchange account you own, once the bookmaker confirms the bet. On a bonus bet the target is a conversion share you set, and the lay only goes on if the Betfair price available hits it. There are three separate blocks for bonus, promo and cash bets, and each is off until you turn it on. It never lays a tote bet, because a tote approximate is not a locked price.
Outside that, B337 places no bets on the exchange, so hedging a sports bonus bet is yours to place. The no-exchange route on this page is hand placed from start to finish: the board shows both prices, and both legs are yours to put on. B337 is software you run on your own computer; it bets only in accounts you hold, on the rules you set, it never holds your funds, and it places nothing while the computer is off. It works only with bonus bets a bookmaker has already put on your account, and it never creates, unlocks or claims one. Bets placed through B337 use credits, a per-bet usage charge. Bookmaker names are trade marks of their owners. B337 is not affiliated with them. For the full method with an exchange, see matched betting in Australia.
Risk: Betting involves risk. Many bookmakers restrict automated betting in their terms, and any of them may reduce your stakes, void bets or shut the account. No software prevents that. A lay can go unmatched and leave the bet exposed, and there is no guarantee of profit. See responsible gambling for limits and support.