Tax Administration

Activity Statement

A form used by businesses to report and pay GST, PAYG withholding, PAYG instalments, and other tax obligations.


An activity statement is a form issued by the ATO to businesses and individuals with certain tax obligations. The most common type is the Business Activity Statement (BAS), which reports GST, PAYG withholding, PAYG instalments, fringe benefits tax (FBT) instalments, and other amounts. Depending on your turnover and obligations, you may lodge monthly or quarterly.

Quarterly BAS is due 28 days after the end of each quarter (28 October, 28 February, 28 April, and 28 July). Monthly lodgers have their BAS due on the 21st of the following month. Electronic lodgement through the ATO's online services or approved software usually grants an additional 4 weeks for some quarters.

If you only have PAYG instalment obligations (e.g., as an investor receiving income with no tax withheld), the ATO issues an Instalment Activity Statement (IAS) instead of a BAS. The key difference is that an IAS does not include GST reporting. Both types can be lodged and paid online through the ATO's Business Portal or myGov.

How it works

An activity statement is the form the ATO issues to businesses to report and pay their periodic tax obligations in one go, rather than separately. The most common version is the Business Activity Statement (BAS), which bundles GST, PAYG withholding, PAYG instalments, and fringe benefits tax instalments into a single lodgement. Whether you lodge monthly or quarterly depends on your turnover and the specific obligations the ATO has registered against your ABN.

In practice, a small business owner sees this as a recurring quarterly, or monthly, task: tally up GST collected on sales, GST credits on purchases, PAYG withheld from any employees' wages, and any instalment amount, then lodge and pay the net figure. Quarterly BAS is due 28 days after each quarter ends — 28 October, 28 February, 28 April, and 28 July — while monthly lodgers have theirs due on the 21st of the following month. Lodging electronically through the ATO's online services can extend some quarterly deadlines by a further four weeks.

A common point of confusion is the Instalment Activity Statement (IAS), issued to people or entities with PAYG instalment obligations but no GST registration — an investor receiving unfranked income with no tax withheld, for example. An IAS looks similar to a BAS but simply drops the GST reporting component, since that entity isn't registered for GST in the first place. Missing an activity statement deadline attracts a failure-to-lodge penalty separately from any tax owing, so a nil statement still needs to go in on time.

Example: working out a quarterly BAS payment

A small business collects $8,000 in GST on its sales during the July–September quarter and has paid $3,000 in GST as part of its own business purchases, which it can claim back as GST credits. The net GST position for the quarter is $8,000 minus $3,000, which comes to $5,000 owing to the ATO.

That $5,000 net GST figure goes on the Business Activity Statement for the quarter, due 28 October — 28 days after the quarter ends on 30 September. If the business also withheld PAYG tax from an employee's wages during the quarter, that amount is reported and paid on the same BAS rather than separately.

Related Terms

Frequently asked questions

What is Activity Statement?
A form used by businesses to report and pay GST, PAYG withholding, PAYG instalments, and other tax obligations.
What's the difference between a BAS and an IAS?
A BAS reports GST alongside PAYG withholding and instalments; an IAS is for entities with PAYG instalment obligations but no GST registration, so it simply leaves the GST reporting out.
When is a quarterly BAS due?
28 days after the end of each quarter — 28 October, 28 February, 28 April, and 28 July. Lodging electronically through the ATO's online services can extend some of these deadlines by a further four weeks.
What happens if I lodge my activity statement late?
The ATO can apply a failure-to-lodge penalty even if you don't owe any net GST or tax for that period, so a nil activity statement still needs to be lodged on time.
Most searched navigate · open