Preparing and lodging a Business Activity Statement (BAS) is one of the most predictable, highest-stakes jobs an Australian firm runs. For most clients it recurs every quarter (some monthly), and it ties together GST coding, PAYG withholding, PAYG instalments, and any other reportable labels into a single statement to the ATO. Get it right and it is quiet, routine work. Get it wrong and you are dealing with amended statements, general interest charges, and clients who lose confidence in the numbers.
The trouble starts when BAS lives in one person’s head or in a spreadsheet that only they understand. Coding gets reviewed inconsistently, GST control accounts drift, a client approval gets skipped, and a deadline slips because nobody was sure whose turn it was. A repeatable process fixes that: the same steps, the same review, the same client touchpoints, every period, no matter who picks up the job.
When to run it
Run the BAS job on each client’s reporting cycle, usually quarterly with due dates following the ATO’s quarterly schedule, or monthly for clients on a monthly GST cycle. Note that lodgement and payment dates often differ depending on whether you lodge as a registered tax or BAS agent. Assign a clear owner for each client so the job is not left unclaimed, and start early enough that draft review and client approval can happen before the due date rather than against it.
How to run it in Tidyflow
Save this checklist as a reusable job template so every BAS engagement starts identically. Each step becomes a subtask your team checks off, from reconciling accounts through to saving the lodged statement and workpapers. Set the job to recur on the client’s quarterly or monthly cycle so it generates automatically when the period closes. The client-facing steps (approving the draft BAS, clarifying uncoded transactions, confirming payment method) go out as client requests completed in the portal, and supporting reconciliations, approvals, and the lodged form are kept together in document management for your records. Connecting Xero or QuickBooks Online keeps the underlying figures close to the reconciliation work.
Common pitfalls
- Lodging before bank, credit card, and loan accounts are fully reconciled, so GST totals are built on incomplete data.
- GST coding errors on capital purchases, imports, and adjustments that quietly understate or overstate the net position.
- GST control accounts (GST collected and GST paid) not reconciling to the BAS summary, signalling a coding or timing problem.
- Lodging without documented client approval, leaving no record if a figure is later queried.
- Treating lodgement as the end: confirmation, payment due date, and archived workpapers all need to be captured before the job is closed.