Arbitrage Betting for Beginners: A Checklist for Your First Lock in Australia

By the AUOdds team · Updated 14 Oct 2026 · 7 min read

Arbitrage betting for beginners is less about clever maths and more about following the same steps, in the same order, every time. A lock happens when licensed Australian bookmakers disagree enough on a price that you can back every outcome and lock in a return at the prices shown. Most guides stop at the theory. This one is a practical checklist: setting up verified accounts, funding them, reading an alert, choosing which leg to place first, handling a leg that fails, and recording the result. Returns per lock are small, and real risks remain. Prices move, stakes get limited, bets can be voided and mistakes happen. Work through each section before you place your first lock.

What does arbitrage betting for beginners actually involve?

Arbitrage betting rests on one idea. When two licensed bookmakers disagree enough on a price, you can back every outcome and lock in a return at the prices shown, whatever the result.

The process matters more than the maths. Search 'arbitrage betting how to' or 'arbitrage betting for dummies' and most results explain implied probability at length, then stop. They rarely say which bet to place first, or what to do when the second bookmaker changes its price while you are typing in your stake.

That gap is where beginners lose money. A lock only holds if every leg is accepted at the stake and price you planned. If one leg fails, you are left holding an ordinary bet, and an ordinary bet can lose.

Returns are also modest. AUOdds data shows 1,532 locks in the last 30 days, with a typical lock of 1.9%. On a $200 total stake, that is about $3.80. The aim of your first lock is not the return. It is learning a routine you can repeat without errors.

Treat this as an arb betting guide in checklist form, and work through it in order:

• Set up verified accounts with licensed bookmakers
• Fund them before you need them
• Read an alert properly
• Place the riskier leg first
• Know your plan if a leg fails
• Check confirmations and record results

How do you set up and fund your bookmaker accounts?

Start with legality. Only use bookmakers licensed in Australia. The ACMA offers a way to check whether a gambling operator is legal (ACMA-LEGAL), and it takes about a minute. Offshore sites are off the table.

Next, get every account fully verified before you look at a single alert. Verification confirms your identity, and an unverified account can hold up a deposit or withdrawal at the worst moment. Locks often last only minutes, so there is no time to upload a photo of your driver licence mid-bet.

Your setup checklist:

• Open accounts with several licensed bookmakers. More accounts mean more locks you can act on. Two is the bare minimum for a two-outcome market.
• Complete verification on each one. Use your real name and details, and keep them consistent across every account.
• Fund each account in advance. Split your bankroll so each account holds enough for a typical leg. A lock you cannot fund is a lock you miss.
• Set deposit limits. Pick an amount you can afford to have tied up, and set it as a limit in each account.
• Check your price-change settings. If a bookmaker lets you choose whether to accept price changes automatically, turn that off so a bet is not struck at a worse price without you noticing.
• Practise the bet slip. Know where the stake box is and what the confirmation screen looks like.

Keep a short note of each account's balance. Before you act on a lock, glance at it so you know both legs can be covered.

How do you read a lock alert before you bet?

An AUOdds alert lists the event, the market, each outcome, the bookmaker offering the best price on it, and the exact stake for each outcome. Prices refresh about every 10 seconds across about 15,000 prices from nine bookmakers, but a price can still move after you see it.

Before betting, confirm these five things on the bookmaker's own screen:

• The event and start time
• The exact market (match winner, not first set winner)
• The selection name
• The price, to two decimal places
• The settlement rules that matter, such as how a retirement or abandonment is treated

Worked example. A tennis match has two outcomes. Bookmaker A offers 2.10 on Player One. Bookmaker B offers 2.00 on Player Two.

Add the implied probabilities: 1 ÷ 2.10 = 0.4762 and 1 ÷ 2.00 = 0.5000, for a total of 0.9762. Because the total is under 1.0000, a lock exists, worth about 2.4%.

With $200 in total:

• $97.56 on Player One at 2.10 returns $204.88
• $102.44 on Player Two at 2.00 returns $204.88

Either way you get back $204.88, a return of $4.88 at the prices shown.

One warning. If the two bookmakers settle the market differently, for example when a player retires injured, the outcomes may not line up and the lock may not be a true lock. When the rules differ or you cannot find them, skip it. There will be another.

Which leg should you place first, and why?

This is the step most beginner guides leave out. Always place the riskier leg first. That is the bet most likely to be refused, cut back or repriced.

How to recognise the riskier leg:

• The outlier price. If one bookmaker is well above the rest of the market, that price is the most likely to be corrected.
• The account more likely to be limited. If one bookmaker has already reduced your maximum stake, place that leg first.
• The larger stake. A bigger bet is more likely to be partly accepted.
• The thinner market. Smaller events and niche markets tend to move faster.

Why the order matters: if the first leg is rejected, you have lost nothing and simply walk away. If it is accepted in full, place the second leg straight away.

In the tennis example, suppose other bookmakers offer 1.90 to 1.95 on Player One. Bookmaker A's 2.10 is the outlier, so place the $97.56 there first.

Now suppose Bookmaker A accepts only $50. Rescale the second leg to match: $50 × 2.10 = $105, and $105 ÷ 2.00 = $52.50 on Player Two. Your total outlay is $102.50 and either result returns $105, so you still lock in $2.50 at the prices shown.

Have both bet slips open before you start, so the gap between legs is seconds, not minutes. Online in-play betting is not offered to Australians, so every lock is pre-match. Place both legs well before the start time, not in the final rush.

What should you do if a leg fails or the price moves?

Decide your plan before you bet, not while your heart is racing. Here are the common failures and a sensible response to each.

The second price drops, but a lock remains. Say Player Two moves from 2.00 to 1.95 after your first leg is placed. Check the total: 0.4762 + 0.5128 = 0.9890, still under 1. Restake to cover the same return: $204.88 ÷ 1.95 = $105.07. Your outlay becomes $202.63 and either result returns $204.88, about $2.25 on the prices shown.

The second price drops below a lock. Now Player Two is 1.85. Covering still makes sense: $204.88 ÷ 1.85 = $110.75, for a total outlay of $208.31 and a return of $204.88 either way. That is a known loss of $3.43. The alternative is leaving $97.56 on Player One as a straight bet, which could lose the full amount. For most people, the small known loss is the better choice.

The second bookmaker rejects or limits your stake. Check whether another licensed bookmaker where you hold an account offers a covering price on the same outcome. Then rerun the numbers.

A leg is voided later. Settlement rules vary between bookmakers, so read each one's terms. If one leg is refunded and the other stands, you are left with a single bet. This is why checking the rules before you start matters.

You make a mistake. If you back the wrong selection or market, cover the exposure at the best price available, accept the cost and move on. Never chase it with a bigger bet.

Set yourself a maximum acceptable loss per lock, such as $5, and stick to it.

How should you check confirmations, record results and stay in control?

A bet is not placed until the bookmaker confirms it. After each leg, open your bets and check the event, market, selection, price and stake. Take a screenshot of each confirmation in case you need it later.

Then log the lock. A simple spreadsheet is enough. Record:

• Date and event
• Market and selection
• Bookmaker
• Price and stake for each leg
• Expected return at the prices shown
• Actual result
• Notes on anything that went wrong

Once a week, compare your records with your account balances. Small differences usually point to a mistake you can learn from, such as a price that changed between the alert and the bet slip.

The ATO publishes guidance on how gambling winnings are treated (ATO-IT2655, ATO-WINNINGS). Read it, and talk to a registered tax agent if you are unsure how it applies to you. Good records make that conversation easy.

A responsible gambling reminder. Gambling is for adults 18 and over only. Set deposit limits and keep within money you can afford to have tied up. If betting stops feeling under control, BetStop, the National Self-Exclusion Register, lets you exclude yourself from all licensed Australian online and phone bookmakers in one step (ACMA-BETSTOP, BETSTOP). Gambling Help Online offers free and confidential support, and the Department of Social Services has more information on gambling help (DSS-GAMBLING).

Frequently asked questions

Sources

1. Check if a gambling operator is legal, Australian Communications and Media Authority
2. Taxation Ruling IT 2655: gambling and betting winnings, Australian Taxation Office
3. Crypto asset prizes and gambling winnings, Australian Taxation Office
4. BetStop: the National Self-Exclusion Register, Australian Communications and Media Authority
5. BetStop, Australian Government
6. Gambling, Department of Social Services

More guides

• Arbitrage Betting Example: 5 Worked Australian Bets
• Compare Odds Australia: Spotting When Prices Lock
• Dutch Betting Horse Racing: Backing the Whole Field
• Arbitrage Betting Australia Reddit: Top Questions Answered

18+ only. Betting involves risk, and prices and limits can change before you place a bet. If gambling isn't fun any more, Gambling Help Online (1800 858 858) is free and confidential, and BetStop lets you exclude yourself from every licensed Australian bookmaker.