What an ABA file is
An ABA file (Australian Bankers' Association) is a plain-text file in a fixed-width format that every Australian business bank accepts for batch payments. You generate the file with your list of supplier payments, upload it to your bank's online banking, and the bank executes every payment in one batch.
This is how every Australian SME of meaningful size pays suppliers — it is the single biggest time-saver in AP.
Creating a payment run
From Accounting → Payment Runs → New run:
- Pick the source bank account (the account that will be debited)
- Pick the payment date (when you want the bank to process the batch)
- Select the bills to include — the list defaults to "all due in the next 14 days", but you can filter by supplier, amount, or due date
- Review the totals at the bottom
- Click Generate ABA file
The file downloads as .aba (e.g. payment_run_2026_05_21.aba).
OneBookPlus stages the bills as Awaiting confirmation at this point — they are not yet marked paid. The journal posting waits until you confirm the run has been processed by the bank.
Uploading the file to your bank
Every bank has slightly different navigation, but the pattern is the same:
- CBA: NetBank Business → Pay & Transfer → Upload a file (ABA / CEMTEX)
- Westpac: Westpac Live Corporate → Payments → Import file
- NAB: NAB Connect → File Services → Upload file
- ANZ: ANZ Transactive → File import → ABA
- Macquarie: Macquarie Business Banking → Payments → Upload payment file
Upload, authorise with your bank's usual approver workflow (often two-person sign-off on high-value batches), and the bank schedules the payments for the date in the file.
Confirming the run
Back in OneBookPlus, on the payment run page, click Mark as processed. This posts the journal:
- Dr Accounts Payable for the total amount
- Cr Bank for the total amount
Every bill in the run flips to Paid. When the bank feed brings the matching debit through, the reconciliation workbench auto-matches it to the payment run as a single line — no per-bill reconciliation needed.
Supplier banking details
For a supplier to be included in a payment run they need BSB and account number recorded against their contact record. The payment run page flags any selected supplier missing bank details and refuses to generate the file until they are added.
Withholding tax
If any supplier is missing an ABN (or has an ABN that fails the ATO ABN lookup), the system flags them under TAA 1953 s 12-190 — payments to suppliers without a valid ABN are subject to 47% withholding. The payment run lets you either fix the ABN, withhold tax automatically, or exclude the supplier from the batch.