Types of Activity Statements¶

There are two main types of Activity Statement, and the difference between them comes down to one thing — GST.

The BAS (business activity statement) is the version that includes GST, and it usually reports other obligations such as PAYG withholding and PAYG instalments at the same time. The IAS (instalment activity statement) is the version with no GST — it is used to report obligations like PAYG instalments or PAYG withholding on their own.

In one line

The BAS includes GST (and usually other obligations too); the IAS has no GST and reports things like PAYG on their own.

Why this matters¶

When people talk about "doing the BAS", they often mean any Activity Statement. But knowing whether you have a BAS or an IAS tells you at a glance whether GST is part of the picture. That helps you understand what the Australian Taxation Office (ATO) expects from you and what to check before you lodge.

What you will learn¶

The two main types of Activity Statement
What a BAS covers
What an IAS covers and how it differs from a BAS

Understanding the concept¶

Both statements do the same basic job — report and pay tax to the ATO. The difference is what they contain.

BAS — business activity statement

The BAS is the one you get when you are registered for GST. It has sections for the GST you collected and the GST you paid, and it usually carries your other obligations too, such as:

PAYG withholding — tax you held back from employees' pay, and
PAYG instalments — pre-payments towards your own income tax.

So a BAS often brings GST and PAYG together on the one form.

IAS — instalment activity statement

The IAS is the one you get when you have obligations to report but no GST. It looks similar to a BAS but simply leaves the GST sections out. It is used for things like:

PAYG instalments on their own, or
PAYG withholding on its own (for example, a business with staff that is not registered for GST).

The simplest way to remember it: BAS = with GST; IAS = without GST.

For accountants & bookkeepers

Both are Activity Statements; the ATO selects the form from the client's active roles. A GST role produces a BAS, which commonly also carries the PAYG withholding and PAYG instalment labels. Without a GST role, PAYG obligations are reported on an IAS. Reporting cycles can differ too — for instance, a GST-registered business reporting GST quarterly but PAYG withholding monthly may receive monthly IAS forms between its quarterly BAS forms.

Example¶

Priya's cafe is registered for GST and has staff, so the ATO issues her a BAS each quarter — GST plus the PAYG withholding from her staff's wages, all on the one form.

Sam's smaller side business is not registered for GST but does withhold tax from one part-time worker. Because there is no GST to report, the ATO issues Sam an IAS — the same style of statement, just without the GST sections.

Same family of forms, but Priya's includes GST and Sam's does not. That single difference is what separates a BAS from an IAS.

Common mistakes¶

Calling every statement a "BAS" — if there is no GST, it is an IAS.
Thinking the IAS is a completely different, unrelated form — it is an Activity Statement too, just without the GST sections.
Assuming a BAS is only about GST — it usually carries PAYG obligations as well.

How this works in myaccountant¶

In the app — myaccountant prepares the right statement for your business from your data. If you are registered for GST it builds a BAS with your GST and PAYG figures; if you are not, it prepares the relevant statement without GST. You review it and lodge it to the ATO from within the app.

Key points¶

There are two main types of Activity Statement — the BAS and the IAS.
The BAS includes GST and usually reports PAYG obligations too.
The IAS has no GST and reports obligations like PAYG on their own.
The difference between them comes down to whether GST is included.
The ATO issues the right one for your business based on your registrations.

Learn next¶

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

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