GDP adjusted PAYG and GST instalment amounts

This overview explains how and why the gross domestic product (GDP) adjustment is applied to pay as you go (PAYG) and goods and services tax (GST) instalment amounts, and what to do if you think this will impact your tax liability.


The information given in this fact sheet is based on a balancing date of 30 June, which is when the majority of taxpayers in Australia balance their accounts. For most taxpayers, the term income year used in this publication refers to a financial year (1 July to 30 June).

Eligible taxpayers who report PAYG instalments or GST quarterly have the option of paying instalment amounts that we calculate for them. These amounts are printed on your quarterly activity statement or instalment notice.

We calculate these instalment amounts from information you have previously reported. We adjust these figures to take into account likely growth in your business and investment income (for PAYG) or in your GST net amount. This adjustment is based on growth in Australia's economy, as measured by GDP.

Why are instalment amounts adjusted?

The information we use to calculate your instalment amounts is generally taken from your most recently assessed income tax return (for PAYG instalments) or annual GST return (for GST).

As PAYG and GST instalment amounts are intended to reflect your expected tax liabilities for the current income year as accurately as possible, we adjust the instalment amounts to reflect expected changes in the economy.

If instalment amounts were solely based on your previous tax situation without any adjustment, they might not cover your actual tax liability – leaving you with an additional payment to make when you lodge your annual return.

    Last modified: 22 Jun 2016QC 16312