If you do your own books, categorising transactions is where the hours go. Every coffee, every subscription, every payment has to be assigned to an account before your reports and BAS mean anything. The good news: most of it can be done automatically — and you don't need to hire a bookkeeper to get there.
Why categorising matters
"Categorising" (also called coding) is assigning each transaction to an account: income, software, motor vehicle, bank fees, and so on. It matters because your BAS and tax return are built directly from these categories. Miscategorise, and your GST and deductions are wrong. Categorise accurately, and the rest of your compliance largely takes care of itself.
The three ways to categorise
- Manually — you assign every transaction yourself. Accurate, but slow, and the same vendors come up again and again.
- With rules — you tell the software "anything from this vendor is this category," and it applies automatically forever after.
- With AI — for transactions no rule covers, an AI model reads the description and suggests the most likely category.
Good software combines all three so you do the least possible manual work.
How auto-coding actually works
The most effective approach is layered, each layer catching what the last didn't:
| Layer | What it does | Best at |
|---|---|---|
| 1. Coding rules | Match a known vendor, apply its category instantly | Recurring suppliers |
| 2. Learning model | Learns from how you've categorised before | New vendors similar to old ones |
| 3. AI (LLM) | Reads the description and infers the category | One-off and ambiguous transactions |
Run together, these typically categorise 80% or more of transactions automatically, leaving you to review only the exceptions. See how AI bookkeeping works.
The "blank page" problem — and a day-one head start
Most accounting software hands you an empty chart of accounts and expects you to teach it every vendor from scratch. For a non-accountant, that's the hardest part. ReconLink ships with a 139-vendor default coding pack built in — the common Australian banks, telcos, fuel, software and retail vendors are recognised on your very first import. You start with automation working, not a blank page. You can also build your own coding rules for the vendors specific to your business.
Keeping it accurate
Automation is only useful if it's correct, so the right design keeps a human in the loop:
- Review the transactions the system wasn't confident about
- Confirm or correct AI suggestions — corrections teach the system for next time
- Spot-check categorised transactions before you lodge your BAS
The goal isn't "no review" — it's "review the few, not the many."
Putting it together
For a sole trader or small business owner, automatic categorisation is the difference between dreading your books and finishing them in an evening. Import your statements, let rules and AI do the bulk, review the exceptions, and your BAS figures are ready. ReconLink's Solo plan is built for one self-filing business and includes a 30-day free trial with no card — see pricing or start free.
Frequently asked questions
Is automatic categorisation accurate enough to rely on?
For the bulk of routine transactions, yes — especially recurring vendors handled by rules, which are deterministic. The sensible workflow is to let automation handle the majority and review the exceptions and any low-confidence AI suggestions before lodging.
Do I have to set up rules myself?
You can, but you don't have to start from zero. ReconLink recognises 139 common Australian vendors out of the box, and you add rules only for vendors unique to your business.
What happens when the AI gets a category wrong?
You correct it, and that correction improves future suggestions. Because you review before lodging, a wrong suggestion is caught at the review step rather than flowing through to your BAS.
This article is general information for Australian small business owners, not tax advice. Confirm your specific GST and record-keeping obligations with the ATO or a registered tax or BAS agent.