No bookmaker in Australia has the best odds on everything. The top price on a runner or a team moves from one bookmaker to another by sport, by market, by race and by the minute. The bookmaker with the best price on one bet is not necessarily the one with the best price on the next. The useful question is which bookmaker has the best price on this bet at the moment you place it.
You can answer it, and measure each bookmaker's margin yourself, with nothing more than the prices and 1 / decimal odds, which how betting odds work explains.
Why bookmakers have different odds on the same race
Each bookmaker reaches its prices its own way. Some compile their own and others follow a wider market and add their own margin, the split sharp vs soft bookmakers explains. Each also runs its own book: a bookmaker holding a lot of money on one runner shortens it, while one that has taken little on it has no reason to. And they move at different speeds, so for a while after news breaks one bookmaker can still show the old price. How bookmakers set odds covers the process.
Example: one six-runner race at three bookmakers at the same moment. Illustrative prices, not a real race.
| Runner | Bookmaker A | Bookmaker B | Bookmaker C | Best price |
|---|---|---|---|---|
| Runner 1 | $3.10 | $3.25 | $3.15 | $3.25 (B) |
| Runner 2 | $3.80 | $3.70 | $4.10 | $4.10 (C) |
| Runner 3 | $5.20 | $4.60 | $4.90 | $5.20 (A) |
| Runner 4 | $6.00 | $6.50 | $6.25 | $6.50 (B) |
| Runner 5 | $7.50 | $8.00 | $8.50 | $8.50 (C) |
| Runner 6 | $13.00 | $11.00 | $12.00 | $13.00 (A) |
Each bookmaker has the top price on two runners. A punter loyal to any one of them takes less than the best price on four runners out of six.
Measuring each bookmaker's margin on the same race
The margin is the amount by which a market's implied chances add up to more than 100%, so measuring it takes one sum per bookmaker: add 1 / price across every runner. For the same race:
| Bookmaker A | Bookmaker B | Bookmaker C | Best prices combined | |
|---|---|---|---|---|
| Market total | 115.50% | 116.51% | 112.64% | 109.23% |
| Margin | 15.50% | 16.51% | 12.64% | 9.23% |
| Average return per $1 | 86.6c | 85.8c | 88.8c | 91.5c |
Working for Bookmaker C: 1 / 3.15 + 1 / 4.10 + 1 / 4.90 + 1 / 6.25 + 1 / 8.50 + 1 / 12.00 = 0.31746 + 0.24390 + 0.20408 + 0.16000 + 0.11765 + 0.08333 = 1.12642, or 112.64%. If the margin is spread evenly, each $1 bet returns 100 / 112.64 = 88.8 cents on average.
Bookmaker C runs the tightest market by almost three points, yet it has the top price on only two runners. And taking the best price on every runner, wherever it sits, makes a cheaper market than any one bookmaker offers: 109.23%. The bookmaker margin calculator does the sum for a market of any size, and market percentage explains how to read a race's total.
A comparison is only fair when four things hold:
- The same market: the same race or game, the same bet type and every outcome, the draw and every runner still in the race included.
- The same moment: prices move, so read them within a minute or two of each other.
- One bookmaker per total: a market of best prices is a separate figure, not a bookmaker's margin.
- A record: write down the date and the time before the start, and keep every sample.
Risk: Betting involves risk. A cheaper market costs you less on average, but every bet in it still wins or loses in full, and a bookmaker can cap your stake under its terms. See responsible gambling for limits and support.
Lowest margin bookmaker: why the answer changes by market
One race says little about a bookmaker. Two-way head to head and line markets on big games draw close comparison between bookmakers, which tends to press their margins down, while player props, exotics and same game multis draw less. Feature races draw more money and attention than midweek races, which can tighten their markets. Bookmaker margin explains why market types differ. These are patterns to measure on a dated sample, never facts about a brand, and the ranking can flip between them:
| Sample (illustrative) | Bookmaker A | Bookmaker B | Bookmaker C | Lowest |
|---|---|---|---|---|
| 8 Saturday metropolitan races, 10 minutes before the jump | 113.2% | 114.0% | 111.8% | C |
| 8 midweek country races, 10 minutes before the jump | 122.5% | 118.9% | 124.1% | B |
| 9 AFL head to head markets, an hour before the bounce | 104.4% | 105.1% | 105.6% | A |
| 30 AFL disposal over/under lines on the same games | 111.0% | 108.6% | 112.3% | B |
These are made-up averages to show the method, not a measurement of any bookmaker or market. The leader changes from one row to the next, which is the point: a margin belongs to a market at a moment, not to a brand.
Some market types do not total this way. Where an exotic such as a trifecta is a tote bet, or is paid at a tote dividend, there is no fixed price to add up before the race. Its cost is the pool's commission, and the dividend is not known until it is declared. A same game multi has one price for a set of linked legs, so compare the price for the identical legs at each bookmaker instead. A milestone market such as 25+ disposals prices only the yes side, and several players can land it, so it has no total to compare.
The best price on one bet and across a season
On one bet the gap is plain. $20 on Runner 3 returns $20 x 5.20 = $104 at Bookmaker A and $20 x 4.60 = $92 at Bookmaker B: $12 more for the same result.
Across a season the same kind of gap works on every bet. A price 5% longer raises every winning return by 5%, so it raises the average return on all your bets by 5% as well. Say you stake $5,000 over a season in $20 bets, at prices that return 88 cents per dollar on average, or $4,400. Prices 5% longer return $4,400 x 1.05 = $4,620, and the season's expected cost falls from $600 to $380. These are illustrative figures, and line shopping works the maths in full.
Risk: Betting involves risk. A better price lowers the cost of a bet without changing how often it wins, so a season of best prices can still finish behind, and there is no guarantee of profit. See responsible gambling for limits and support.
Shared platforms, shared licence holders and the same price twice
Another account is not always another price. Many smaller brands run on shared betting platforms, and a platform can supply the same prices to every brand on it, so two brands can show identical prices on every runner. The white label bookmaker entry explains how that works.
Some brands also share a licence holder. ACMA's register of licensed wagering providers lists each trading name with its licence holder and licensing authority. It does not show which platform supplies a brand's prices, so only their prices side by side can tell you whether two brands price alike. How a bookmaker treats related accounts is set by its own terms, so read them: many bookmakers restrict or prohibit multiple or related accounts, and a bookmaker can limit stakes, void bets or close an account. Never open a sister brand, or any new account, to get around a restriction or a limit, and open accounts only in your own name, to place your own bets.
Boosts and promotions are not a price comparison
Compare standard prices with standard prices. A boosted price, a bonus bet or a money-back offer is a promotion with its own terms, such as a maximum stake, the markets it covers, or a payout in bonus bets rather than cash. It changes the terms of one bet, but it is not the bookmaker's price on that market and says nothing about its prices on the next bet. Value a promotion on its own terms against a fair price, as odds boosts explained does for boosts, and keep it out of the comparison.
Some racing bet types pay a price set after you bet, such as the starting price, top fluc, best tote or best of the best, under each bookmaker's own terms. Betting odds types explains each one: compare them as products, not as prices.
Why the price shown is not always the price you get
The best price on a screen is an offer, and it can change before your bet lands:
- Prices move. The difference between the price you expected and the price you got is called price slippage, so check the bet slip before you confirm.
- Stakes can be capped. Each market carries a maximum bet, and a bookmaker can take only part of a stake or limit an account under its terms, which why bookmakers restrict accounts explains.
- A late scratching can cut a winning fixed-odds racing bet by a deduction the stewards declare.
On racing, a bookmaker can be obliged to take an eligible fixed-odds bet at its displayed price, up to a set amount it must stand to lose: the minimum bet limit. Racing Victoria's limits have applied since 1 October 2016 to approved off-course operators on Victorian thoroughbred races, for bets placed after the Final Acceptances deadline. They are $2,000 to lose on a win, win-place or each way bet and $800 on a place bet on metropolitan races, and $1,000 and $400 on other races.
Racing NSW, Racing Queensland (all three codes) and, in Western Australia, the Gaming and Wagering Commission set their own, each with its own exclusions. Racing NSW's published FAQ excludes betting exchange and bonus bets, and Racing Queensland's page excludes betting exchange bets. Queensland has required operators to part-accept a bet up to the limit, instead of rejecting all of it, since 1 July 2025 (all checked October 2026). These schemes cover racing bets only, and minimum bet limits sets out each scheme.
Mistakes that cost you the better price
| Mistake | What it costs | The fix |
|---|---|---|
| Betting with one bookmaker out of habit | Runner 3 at $4.60 instead of $5.20: $12 less on a $20 winner | Check the same bet at each bookmaker you hold an account with |
| Comparing prices read at different times | A price from 20 minutes ago may no longer exist | Compare prices read at the same moment |
| Counting two brands on one platform as two opinions | They can show one price twice | Treat identical prices as one source until they move apart |
| Judging a bookmaker on one market | A tight head to head market says nothing about its props | Measure each market type on a dated sample |
| Chasing a price your account cannot take | A capped stake can make the best price useless at your size | Check that the stake is accepted before relying on the price |
Comparing prices side by side on B337's Terminal
Checking each bookmaker by hand is slow, and the best price can move while you do it. B337's Terminal, its live odds comparison board, sets racing and sports prices from 40+ bookmakers side by side, one column per bookmaker, and picks out the best available price on each runner or selection. Betfair's back and lay prices are shown beside them, with flucs, the history of how each price moved, and closing lines, the last prices before the jump. Not every bookmaker prices every race or game, so the columns follow the market: before you total one bookmaker's prices, make sure it prices the whole field.
Each price is read on a repeating cycle rather than as it changes, so the board can show a price the bookmaker has already moved: confirm it in your bookmaker account before you bet. A free account opens a limited view of the Terminal with live odds, the full set of bookmaker columns starts with Terminal View, and plans and pricing lists what each plan includes. B337 is software, not a bookmaker. Bookmaker names are trade marks of their owners. B337 is not affiliated with them.
For free and confidential support call 1800 858 858 or visit gamblinghelponline.org.au.
Risk: Betting involves risk. The best available price on a board can be gone by the time your bet reaches the bookmaker, and a better price does not stop a bet from losing. See responsible gambling for limits and support.