I sell on eBay and Amazon on the side — does the ATO get my sales figures?

The account started as a wardrobe clear-out. Then it was a few boxes of clearance stock someone had going cheap, then a second account on a different platform, and somewhere in the middle of that it stopped being a clear-out. The money lands in an ordinary personal bank account. There is no ABN. The working assumption has been that the amounts are too small for anyone to be counting, and that a platform headquartered overseas is not handing anything over anyway.

The second half of that assumption has been wrong since 2008, which is when the ATO began collecting this data. The first half is the part worth thinking about now, because the return being lodged this month is the 2025–26 one — the last financial year covered by the program as it currently stands.

What the ATO actually collects

The online selling data-matching program covers every financial year from 2018–19 to 2025–26, and the data is collected annually after each year ends. The two named providers are eBay Australia and New Zealand Pty Ltd and Amazon Commercial Services Pty Ltd. The ATO obtains the data under section 353-10 of Schedule 1 to the Taxation Administration Act 1953 — a coercive information-gathering power, which means the platforms are obliged to hand it over rather than choosing to.

The selection rule is a dollar figure. The ATO collects data from online marketplaces whose registrants sold goods or services with a total annual value of $12,000 or more in the applicable financial year. On its own estimate that comes to between 20,000 and 30,000 account records each financial year, of which roughly 10,000 to 20,000 matched records relate to individuals rather than businesses.

The record is considerably more than a sales total. On the identification side it can include given and surname, date of birth, residential and postal addresses, ABN, email address and contact phone number. On the account side: account name, account identification number, account registration date and type, store type, seller status, IP address, and both the number and the value of sales transactions — annually and month by month. That last detail is the one people underestimate. Monthly figures show the shape of a year, not just its size, and a shape is what separates three busy weeks in December from something running continuously.

One thing the ATO states plainly is worth keeping in view: the data in this program is not used directly to initiate automated compliance activity. It feeds analytical models alongside other ATO-held data, and where it reveals discrepancies between online sales and what was declared, the ATO investigates further. The program's stated purposes include identifying people who may be failing to meet registration or lodgment obligations — specifically, those transitioning from hobby status to carrying on a business, and reviewing entitlement to an ABN.

$12,000 is not a tax-free allowance

This is the most common misreading, and it is an expensive one. The $12,000 is the threshold that decides whose data gets handed to the ATO. It is not an amount you can earn from selling before tax applies, and it does not appear anywhere in the income tax law as one.

The question that decides whether the money is assessable is a different one: are you in business? The ATO's own test has no dollar figure in it at all. The more of these you answer yes to, the more likely it is that your activities are a business — do you intend to be in business; do you intend to and have a prospect of making a profit; is the size or scale of the activity enough to make a profit; are the activities repeated and continuous; and are they planned, organised and carried out in a business-like manner. That last one unpacks into the things a seller usually already has: business records and a separate bank account, advertising and selling to the public rather than to family and friends, business premises, required licences, a business plan or budget, a business name or an ABN.

Generally, a business involves a set of continuous and repeated activities done for the purpose of making a profit — and profit does not have to arrive as money; being paid in goods or services counts. Read against that, buying stock specifically to resell it, repeatedly, at a margin, is the textbook case. A genuine hobby or recreation you don't seek to profit from is not, and stays outside it regardless of how many listings there are.

If the answer is that you are in business, the consequences start at the first dollar, not at $12,000: the income is assessable, it belongs in the business section of the return rather than as 'other income', and an ABN is expected. Separately, GST registration becomes compulsory once GST turnover reaches $75,000, and once you are required to register you have 21 days to do it.

"But I'm only selling my own second-hand things"

Often this is true, and it is the right answer. Household furniture, electrical goods and similar items you kept for your own use or enjoyment are personal use assets. A capital gain on a personal use asset is only subject to CGT if the asset cost more than $10,000 to acquire, and capital losses on personal use assets are ignored entirely — you cannot use the loss on an old sofa to reduce a gain somewhere else.

Two limits on that, though. The first is that it is a capital gains tax rule, and it applies to assets kept for personal use. Goods bought in order to be sold were never personal use assets; their proceeds are ordinary income, and the $10,000 figure has nothing to do with them. The second is practical: the personal answer and the commercial one usually run through the same account and the same bank feed. If half the listings are the contents of a garage and half are stock, the total in the ATO's file is a single number, and the work of separating the two is yours to do rather than theirs.

What is worth doing before 31 October

Start from the platform's own reports rather than the bank statements. Bank deposits are net of fees, refunds and platform holds, and they will not reconcile with the annual sales value in the ATO's file — that figure is gross. Sellers who rebuild the year from their bank account almost always arrive at a number lower than the one the ATO is looking at, and then have to explain the gap.

Then split the year honestly into the two categories above, and answer the business question on the facts as they were, not as they started. Many accounts genuinely change character partway through a year. If the conclusion is that you were in business, the fix is ordinary work: an ABN, the income in the right part of the return, the costs of sale claimed against it, and a check on whether turnover crossed $75,000 at any point.

The calendar matters here. 31 October is the usual deadline to lodge your own return, and if you want to use a registered tax agent's extended lodgment program you need to be on their books before 31 October — engaging one on 1 November does not get you the later date. Correcting a position yourself before a query arrives is a different conversation from answering one after it does.

This is general information current as at 14 September 2026, not advice about a particular account or a particular year. Working out which side of the hobby line an activity sits on depends on the whole picture, and that is exactly what our sole trader and ABN service and our small business accounting service are for. The income tax calculator on this site will show you what adding a year of side income to your wages comes to at the 2026–27 rates while you pull the file together.