An Instalment Activity Statement (IAS) is a simplified ATO reporting form for entities that have PAYG instalments or PAYG withholding obligations but either are not registered for GST or lodge their BAS quarterly and pay withholding monthly.
Who uses an IAS
- Businesses not registered for GST that still have employees (and therefore PAYG withholding obligations).
- Investors or individuals with PAYG instalment obligations but no GST registration.
- Quarterly BAS lodgers who must remit PAYG withholding monthly — they lodge an IAS in the two 'non-BAS' months of each quarter.
- Entities in their first period of GST registration, where only part of the quarter falls within the registration.
IAS vs BAS
An IAS contains a strict subset of BAS labels. There are no GST labels (G1–G22) and no label 1A/1B. Typical IAS labels are W1 (total salary and wages subject to withholding), W2 (PAYG withholding), and T1/T2 (PAYG instalments). This makes it significantly shorter to complete than a full BAS.
Typical scenario
A small investment trust has no employees and is not registered for GST, but the ATO has entered it into the PAYG instalment system after its first profitable tax return. It lodges quarterly IASs reporting its instalment amount at T7, with no withholding labels.
Due dates
Monthly IAS lodgements are due on the 21st of the following month. Quarterly IAS due dates match BAS due dates: 28 days after period end, with agent concessions. Late lodgement incurs failure-to-lodge penalties in the same way as a BAS.
Can I move from monthly IAS to quarterly?
Yes. If your PAYG withholding for the prior year was $25,000 or less, you can elect to report and pay quarterly rather than monthly. Contact the ATO or your tax agent to change the reporting cycle.