Arbitrage Betting and Taxes in Australia: What the ATO Says
- The ATO generally treats gambling winnings, including arbitrage returns, as not assessable income for people betting as a hobby.
- Arbitrage betting can be treated as a business in some cases, depending on scale, organisation, purpose and how much you rely on it.
- Recreational betting losses are generally not deductible, so voided legs and staking mistakes come straight out of your own pocket.
- A log of every lock helps you check results and gives a tax agent something concrete if your circumstances change.
- This guide is general information, not tax advice, so ask a registered tax agent about your own situation.
Arbitrage betting and taxes is a topic most search results answer poorly for Australians, because page one is mostly US answers that don't apply here. This guide sticks to the Australian position. It covers what the ATO says about gambling winnings, why recreational punters generally don't pay tax on them, and where the line between a hobby and a business sits. It also covers which records are worth keeping as you build locks, and how all this fits with the legality of arbing here. This is general information, not tax advice. Tax depends on your own circumstances. If you're unsure where you stand, ask a registered tax agent or the ATO.
- How do arbitrage betting and taxes work in Australia?
- Can arbing ever be treated as a business by the ATO?
- What factors does the ATO weigh in the hobby versus business question?
- What records should arbers keep, and why?
- Is arbitrage betting legal in Australia, and does that affect tax?
- When should you get tax advice, and what else should you watch?
How do arbitrage betting and taxes work in Australia?
For most Australians, arbitrage betting and taxes are a short conversation. The ATO's guidance on gambling winnings says winnings from gambling are generally not assessable income if you're betting as a hobby or recreational pursuit. That position goes back to Taxation Ruling IT 2655, which deals with when betting is treated as carrying on a business rather than a pastime.
Arbitrage doesn't get a special category. A lock is still a set of ordinary bets placed with bookmakers, one on each outcome. The stakes are sized so the return is locked in at the prices shown. The tax question is the same one any punter faces: are you a recreational bettor, or are you running a betting business?
Why do arbers ask about it more than casual punters? Mainly because the returns look steady. AUOdds data shows that across 2,772 locks in the last 30 days, a typical lock sat around 1.5%. Small, repeatable margins feel more like income than a lucky multi does, so it's natural to wonder whether the ATO sees it the same way.
There's a flip side worth knowing. If your winnings aren't assessable, your betting losses generally aren't deductible either. That matters in arbing, because losing days happen:
- A price drifts before your second leg goes on.
- A stake gets limited to a fraction of what you wanted.
- A bet is voided under a bookmaker's rules.
- You key in the wrong amount.
None of this is personal tax advice. It's the general position, and your own circumstances decide how it applies to you.
Can arbing ever be treated as a business by the ATO?
It can, but it isn't the default. IT 2655 recognises that a person can be carrying on a business of betting, and it looks at the whole picture rather than one feature. The ATO's general guidance points the same way: winnings are usually outside the tax system unless your betting amounts to a business.
The tricky part for arbers is that arbitrage is systematic by nature. You use a calculator, split stakes precisely and compare prices across books. Some people assume that alone makes it a business.
It doesn't settle the question on its own. A careful hobbyist can be well organised. The ruling weighs a combination of factors and considers whether the activity as a whole looks like a commercial enterprise.
It also helps to separate betting winnings from other money that can come up around betting. Being paid to write about betting, run a tipping service or promote a product is a different activity. Don't assume it gets the same treatment as winnings from your own bets.
A useful way to think about it:
- Hobby arbing: you place locks around your normal life, with money you can afford to set aside, and the activity is a side interest.
- Possible business: betting is central to how you support yourself. It's run at a large scale, with commercial-style organisation and a clear profit-making purpose.
Most people sit comfortably in the first group. If you're drifting towards the second, get a registered tax agent involved rather than guessing.
What factors does the ATO weigh in the hobby versus business question?
IT 2655 discusses a range of indicators. No single one decides the matter, and they're considered together. In plain terms, the ones most relevant to arbitrage are:
- Scale: the size of your stakes and turnover, especially compared with your other income and assets.
- Organisation: whether the activity is run in a businesslike way, with systems, records and planning that look commercial.
- Purpose: whether the betting is aimed at making a living, rather than being an interest you pursue.
- Regularity: how often and how consistently you bet.
- Reliance: whether betting is a main source of your livelihood.
Two quick sketches show how differently people can land.
Sam is an electrician who checks lock alerts at lunch and in the evening. He places a few locks a week with total stakes of $200 to $400 and keeps a simple spreadsheet. He treats it as a side interest alongside a full-time job. On those facts, his activity looks recreational.
Jordan has left salaried work and bets across every available bookmaker most days. Jordan turns over large sums each month and relies on the results to pay the bills. That situation has more of the features the ruling discusses. A registered tax agent should look at the full picture in a case like this.
Neither sketch is a ruling on anyone's actual affairs. The point is that the same activity can look very different depending on scale and reliance. If you're unsure which side of the line you're near, get professional advice or ask the ATO directly.
What records should arbers keep, and why?
Good records are worth keeping even if your winnings aren't taxed. They help you check that each lock returned what it should and spot errors early. They also give a tax agent something concrete if your circumstances change.
Here's a short worked example. Suppose a tennis match shows Player A at 2.05 with one bookmaker and Player B at 2.02 with another. The implied probabilities are 1 ÷ 2.05 = 0.4878 and 1 ÷ 2.02 = 0.4950, totalling 0.9828. Because that's under 1, the prices lock.
With $500 in total:
- Player A stake: $500 × 0.4878 ÷ 0.9828 = $248.17, returning about $508.75
- Player B stake: $500 × 0.4950 ÷ 0.9828 = $251.83, returning about $508.70
That's roughly $8.70 back on $500, about 1.7%, at the prices shown. Now suppose Player B's price had dropped to 1.95 before you placed the second leg. The total would have been above 1, the lock would have been gone, and your record should show that too.
For each lock, a simple log might include:
- Date, event and market
- Bookmaker, odds and stake for each leg
- Time each leg was placed
- Result, return and net figure
- Notes on anything unusual: voided legs, limited stakes, price changes
Keep deposit and withdrawal records alongside your bet history. Bookmaker transaction histories are useful, but each one only shows its own leg. Your own log ties both legs of each lock together.
Is arbitrage betting legal in Australia, and does that affect tax?
A common follow-up is: is arbitrage betting legal in Australia? Adults can bet with licensed Australian bookmakers, and placing bets on different outcomes at different books isn't itself against the law. Bookmakers can still apply their own terms, which may mean limiting stakes or closing accounts. That's a commercial decision, not a legal penalty.
The operator is where legality really matters. The ACMA lets you check whether a gambling operator is legal to offer services to Australians, and it's worth doing before you open any account. Offshore sites that aren't licensed here create problems no tax explanation can fix. Those include weaker protections, uncertain payouts and the chance of losing access to your funds.
For arbitrage betting in Australia, sticking with licensed books also keeps your records clean and consistent. AUOdds tracks about 15,000 prices across nine licensed Australian bookmakers, with prices typically about 10 seconds old. That means locks can be built entirely within the regulated market.
A few practical points:
- Open accounts only with operators you've checked through the ACMA.
- Use your own identity and your own bank accounts for every account.
- Log every bookmaker the same way so your records reconcile.
- Keep copies of bookmaker terms that affect voids or limits.
Legality and tax are separate questions. Using licensed books answers the first. Your own circumstances answer the second, and both deserve a little attention before you scale up.
When should you get tax advice, and what else should you watch?
The general position suits most recreational arbers. Some situations deserve a proper conversation with a registered tax agent:
- Betting has become your main source of income.
- Your turnover is large relative to your other income and assets.
- You've set betting up with commercial features, such as a separate entity or staff.
- You earn money from betting-related activities other than your own winnings.
- You're unsure how the ATO would view your situation and want certainty.
When you talk to an adviser, bring your lock log, your bookmaker transaction histories and a short summary of how you bet. Include how often you bet, your typical stake sizes and how much time it takes. That makes the conversation faster and more useful.
A reminder about the activity itself. Arbitrage locks in a return at the prices shown, but things can still go wrong:
- Prices move between legs.
- Stakes get limited.
- Bets can be voided.
- Human error is easy when you're working fast.
Keep stakes at a level where a mistake won't hurt your finances.
Gambling is for adults 18 and over. If betting stops feeling like something you control, you can use BetStop, the National Self-Exclusion Register. It lets you exclude yourself from all licensed Australian online and phone bookmakers in one step. Gambling Help Online offers free, confidential support. The Department of Social Services also publishes information on gambling and where to find help.
Frequently asked questions
Do I have to declare arbitrage winnings on my tax return?
For most people betting as a hobby, the ATO generally treats gambling winnings as not assessable income, so they don't need to be included. That can change if your betting amounts to carrying on a business. Arbitrage doesn't get its own category, and the same hobby versus business question applies. If you're unsure, ask a registered tax agent.
Can I claim arbitrage losses as a tax deduction?
Generally not, if you're betting recreationally. The same reasoning that keeps hobby winnings out of the tax system generally keeps losses out too. In arbing, losses usually come from price moves between legs, voided bets, limited stakes or mistakes. If you believe you're running a betting business, talk to a tax professional about how that changes things.
Does using alerts or a calculator make my arbing a business?
Not on its own. Tools help you work out stakes accurately, but being organised is only one factor. The ATO looks at the whole picture, including scale, purpose, regularity and whether betting is a main source of your livelihood. A careful hobbyist can use a calculator and still be betting recreationally.
Do US gambling tax rules apply to Australians?
No. Much of what appears in search results about gambling tax relates to the US system, which works differently. Australians should rely on ATO guidance, including Taxation Ruling IT 2655 and the ATO's information on gambling winnings. If you have tax ties to another country, get advice specific to your situation.
Sources
- Taxation Ruling IT 2655: gambling and betting winnings, Australian Taxation Office
- Crypto asset prizes and gambling winnings, Australian Taxation Office
- Check if a gambling operator is legal, Australian Communications and Media Authority
- BetStop: the National Self-Exclusion Register, Australian Communications and Media Authority
- BetStop, Australian Government
- Gambling, Department of Social Services
More guides
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.