Every betting market carries a margin, and almost nobody measures it. On 12 October 2026 we read the prices twelve named Australian bookmakers were showing on 158 upcoming events across 24 sports, and computed the overround in 5,245 individual markets. This page is the result and the method, so the measurement can be checked rather than believed.
One finding is worth stating before the tables. Two well-known brands returned identical figures on every measure we computed, so we went back and compared them price by price: 1,049 selections, 1,049 matches, no exceptions.
How the margin is calculated
Turn each price into an implied chance, which is 1 divided by the decimal price. Add the chances of every outcome in a market. A market with no margin sums to exactly 1.00. Anything above that is the bookmaker's share, and it is called the overround.
Example: a two-way market priced $1.90 and $1.90 implies 52.63% and 52.63%, which sums to 105.26%. The overround is 5.26%, and on a $100 bet that is an expected cost of $5.00.
The same arithmetic runs on any number of outcomes, which is why it can compare a head to head with a player total. The bookmaker margin calculator does it on prices you type in yourself.
What we measured, and what we left out
158 events with usable prices, out of 206 requested, across 24 sports. 3,310 usable markets from 3,993 candidate groups. 5,245 bookmaker-market observations in total, after three exclusions that each remove a way of getting a confident wrong answer.
Stale prices. The feed flags how old each bookmaker's prices are. 379 price records were flagged stale and dropped before anything was computed, so this measures what was on screen at the time rather than what was there yesterday.
Part-priced markets. If a bookmaker prices four of the five outcomes in a market, the sum is short because a price is missing, not because the book is generous. Those are skipped, and counted: between 347 and 619 such skips per bookmaker, which is a large enough number that hiding it would misrepresent the coverage.
Implausible sums. Anything summing below 1.00 or above 1.60 for a single bookmaker is almost always a data problem rather than a price, so it is excluded.
The correction that mattered
The first run of this measurement reported a 27.4% margin on handicap markets. That is not a margin, it is a grouping error, and it is worth describing because anyone repeating this will hit it.
A market in the data can contain several separate books. A totals market carries over 2.5 and under 2.5 and also over 3.5 and under 3.5. Summing all four gives a number near 2.00 that means nothing. So outcomes have to be grouped into real books before anything is added up.
The trap is that the data carries two conventions at once. A totals market prices over and under at the same line, 2.5 and 2.5. A handicap market prices the favourite at minus 4.5 and the underdog at plus 4.5, which are different numbers for the same book. Grouping on the raw line splits that pair and leaves the real market unmeasured, while other sets get merged. Grouping on the absolute value of the line handles both conventions, and the handicap figure fell from 27.4% to 7.12%, which is a believable number.
Note: a measurement that produces a wrong answer confidently is worse than no measurement. The 27.4% figure looked like a finding and would have been published as one.
Margin by bookmaker
Median overround across every market we could measure for each bookmaker, on 12 October 2026. The median rather than the mean, because a handful of wide multi-outcome markets drags an average around.
| Bookmaker | Median margin | Mean margin | Markets measured | Cost per $100, two-way |
|---|---|---|---|---|
| TABtouch | 6.95% | 7.59% | 339 | $6.50 |
| Unibet | 6.95% | 7.34% | 480 | $6.50 |
| TAB | 6.97% | 7.71% | 159 | $6.52 |
| Palmerbet | 7.00% | 7.39% | 350 | $6.54 |
| Ladbrokes | 7.03% | 7.41% | 668 | $6.57 |
| Neds | 7.03% | 7.41% | 668 | $6.57 |
| BetRight | 7.06% | 8.12% | 230 | $6.59 |
| bet365 | 7.07% | 7.01% | 724 | $6.60 |
| PointsBet | 7.10% | 8.18% | 487 | $6.63 |
| Sportsbet | 7.43% | 8.21% | 465 | $6.92 |
| Dabble | 7.84% | 7.96% | 375 | $7.27 |
| Picklebet | 10.11% | 10.55% | 300 | $9.18 |
Eleven of the twelve sit inside 0.89 of a percentage point of each other. That is the first honest conclusion: on average, across everything they price, the major Australian bookmakers charge close to the same.
The final column converts the median margin into what it costs on a $100 bet in a two-way market, which is the figure that means something to a punter. The gap between the narrowest book and Picklebet is $2.68 per $100 staked.
Margin by market type
Averaged across the named bookmakers, weighted by how many markets each contributed.
| Market type | Average margin | Markets |
|---|---|---|
| Total runs | 6.29% | 160 |
| Player receptions | 6.67% | 90 |
| Player receiving yards | 6.82% | 116 |
| Total points | 6.93% | 1,013 |
| Period line | 6.97% | 108 |
| Line | 7.12% | 488 |
| Period total | 7.24% | 346 |
| Head to head | 7.34% | 639 |
| Player hits | 7.63% | 83 |
| Period winner | 7.91% | 245 |
| Player RBIs | 7.94% | 100 |
| Total games | 8.02% | 112 |
The spread here is narrower than the usual advice suggests. The widest market type we measured sits 1.73 points above the narrowest. Markets with many outcomes, such as correct score, were mostly excluded by the plausibility filter, so this table describes the two and three-outcome markets most people bet.
Two brands, one set of prices
Ladbrokes and Neds returned identical numbers on every measure: the same median, the same mean, the same count of markets measured, the same count of markets skipped, the same nineteen market types. Identical aggregates can happen by coincidence. Identical aggregates on five independent measures usually mean you are measuring one thing twice.
So we compared them directly, selection by selection, across 48 events.
| Pair | Selections both priced | Identical prices | Agreement |
|---|---|---|---|
| Ladbrokes and Neds | 1,049 | 1,049 | 100% |
| Unibet and TABtouch | 587 | 544 | 92.67% |
| Sportsbet and TAB | 291 | 40 | 13.75% |
| bet365 and PointsBet | 467 | 26 | 5.57% |
| Betr and BetRight | 0 | 0 | no shared selections |
The bottom two rows are the control, and they are the reason the top row is a finding rather than a curiosity. Two independently priced bookmakers agree on somewhere between one selection in twenty and one in seven. Ladbrokes and Neds agreed on every single one, and the comparison produced no example of a difference because there were none to show.
Unibet and TABtouch at 92.67% is a second pattern of the same kind, at a lower level.
Risk: Betting involves risk. Bookmakers can restrict or close accounts and void bets, prices move, and a positive expected value bet can still lose. A low margin is not a winning bet and there is no guarantee of profit. See responsible gambling for limits and support.
What this means if you shop around
Comparing prices across bookmakers is sound, and it is the single most reliable way to pay less. This measurement just narrows what counts as comparing.
If two brands quote the same number on every selection, holding accounts with both gives you two accounts and one price. On the day we measured, a punter checking twelve brands on a market all twelve priced was looking at fewer independent opinions than the count suggested. Who owns Australian bookmakers covers the corporate side, which we deliberately do not infer from a price measurement.
The second thing worth taking from the table is that the margin differences between the major books are small relative to the difference between a good price and a bad one on any single selection. A 0.89 point spread in average margin is worth less than taking the top price on the market you actually want, which is why which bookmaker has the best odds is a different question from this one.
Repeating this yourself
The method in full: take upcoming events, read every bookmaker's price on every selection, drop prices the feed flags stale, group outcomes into real books by market, absolute line, period and player, keep only the bookmakers that priced every outcome in a group, exclude sums below 1.00 or above 1.60, then take the median per bookmaker.
Three things will change your answer: the sample day, the sports included, and whether you handle the two line conventions. The first two move the number a little. The third moves it from 7% to 27%.
What this does not measure: tote markets, which have no fixed price to sum; markets we could not read in full; and the exchange, where the cost is a commission on winnings rather than an overround, so it is not comparable and is left out rather than quoted alongside.
The prices came from the same board B337 shows on odds comparison, read on a repeating cycle rather than tick by tick, so an individual price can trail the bookmaker's own by the time it is read. That is a limit of any measurement like this one, including the ones that do not mention it.