Common correction scenarios¶

The rest of this module explained the rules. This lesson puts them to work. Below are five mistakes small businesses often make on a Business Activity Statement (BAS), each shown as a short real-world scenario — with how to fix it, and whether you would fix it on a later Activity Statement or revise the original.

A quick reminder before we start. The Australian Taxation Office (ATO) lets you fix many mistakes on your next Activity Statement, within its limits. When a mistake is too big, too old, or outside those limits, you revise the original period instead. Keep these two paths in mind as you read.

Why this matters¶

Seeing the fix worked through on a realistic example makes the rules stick. Next time you spot one of these mistakes in your own books, you will know straight away which path to take — and you will not waste time revising something you could have simply tidied up next time.

What you will learn¶

• How to recognise several common BAS mistakes
• The right fix for each, and whether it is a later-statement correction or a revision
• How the module's ideas fit together

Understanding the concept¶

Two ideas run through every scenario below.

Which way did the mistake go? If you reported or paid too much — for example, you left off a purchase you were entitled to claim, or you claimed too little — that is a "credit" type of mistake, and the ATO generally lets you fix it on a later statement within the period of review. If you reported or paid too little — for example, you over-claimed a GST credit, or left a sale off — that is a "debit" type of mistake, and it can be fixed on a later statement only within the ATO's time and value limits. Beyond those limits, you revise the original period.

Payroll amounts are a little different. Some payroll-related corrections follow their own path, which the scenarios point out where it matters.

Example¶

Each scenario uses round, illustrative amounts. The dollar figures are just to show the shape of the fix — they are not thresholds.

Scenario 1 — a sale left off a BAS¶

Priya runs a cafe. After lodging last quarter's BAS, she realises she forgot to include a catering job. Because the sale was left off, she understated her sales and paid too little GST for that quarter.

The fix: add the missing sale so the GST on it is reported. Leaving a taxable sale off means you reported too little — the "too little" direction. If it is small and recent enough to sit inside the ATO's limits, Priya can pick it up on her next BAS. If it is too big or too old for those limits, she revises the original quarter instead.

Scenario 2 — GST claimed on a GST-free purchase¶

Jordan buys some basic food items for his staff room and, out of habit, claims a GST credit on them. But those items were GST-free, so there was no GST to claim. He has claimed a credit he was not entitled to, which means he paid too little overall.

The fix: remove the credit that should not have been claimed. Over-claiming a credit is the "too little" direction. Jordan can correct it on a later BAS if it fits the ATO's time and value limits for this type of error; if it is outside those limits, he revises the original period.

Scenario 3 — a GST credit claimed twice¶

Sam enters a supplier's bill twice by mistake, so the GST credit on it is claimed twice. Only one credit was ever due, so Sam has over-claimed and paid too little.

The fix: remove the duplicate credit so the purchase is counted once. Like Scenario 2, claiming a credit twice is the "too little" direction. Sam can fix it on a later BAS within the ATO's time and value limits, and revises the original period if it falls outside them.

Scenario 4 — a wrong W2 after a payroll correction¶

Priya fixes a pay run in her payroll after realising an employee's tax was worked out wrongly. That changes the total tax withheld — the amount shown at label W2 on the BAS she already lodged is now wrong.

The fix: payroll amounts follow their own path. If you are simply adjusting the withholding amount you reported, the ATO lets you correct it, and you should keep a written note that you made that choice. But if the real problem is that you did not withhold an amount you should have, that is not fixed on a statement at all — you advise the ATO by letter instead. So for a wrong W2: correct the reported amount and keep a record, and if any amount was never withheld, contact the ATO about that part.

Scenario 5 — a pre-fill that did not match payroll¶

When Jordan starts his BAS, the withholding figure is already filled in for him from his Single Touch Payroll (STP) reporting. This quarter the pre-filled number does not match his own payroll records, because a late pay run had not flowed through yet.

The fix: the pre-filled figure is only a starting point. Jordan checks it against his own payroll records and, where they differ, updates the figure on the BAS to match what he actually reported and paid, then lodges. Because he catches this before lodging, there is nothing to revise — he is simply making sure the statement is right the first time.

Common mistakes¶

• Treating a left-off sale as harmless — it means you reported too little and still needs fixing.
• Assuming every GST over-claim can go on the next BAS — the "too little" direction has time and value limits, and beyond them you revise.
• Trying to fix an amount you never withheld by putting it on a statement — that one is handled by contacting the ATO instead.
• Trusting a pre-filled figure without checking it against your own payroll records.

How this works in myaccountant¶

Key points¶

• A left-off sale means you reported too little — fix it later if it fits the limits, otherwise revise.
• GST claimed on a GST-free purchase is an over-claim — later fix within limits, otherwise revise.
• A GST credit claimed twice is an over-claim — later fix within limits, otherwise revise.
• A wrong W2 from a payroll correction is fixed on the withholding side, with a written note kept.
• An amount you never withheld is handled by contacting the ATO, not on a statement.
• A pre-fill that does not match payroll is corrected before lodging — no revision needed.

Learn next¶

• When to revise a BAS
• Correcting GST errors
• What happens after you revise

General information only — not tax, super or financial advice.