From 1 July 2025, a key change to Australia’s tax laws will take effect: you’ll no longer be able to claim a tax deduction for interest charges imposed by the ATO—specifically the General Interest Charge (GIC) and Shortfall Interest Charge (SIC).

This change was passed by Parliament on 26 March 2025, and it could significantly impact how you manage any outstanding tax debts with the ATO.

Here’s what you need to know and how to prepare.

What’s Changing?

Up until now, if you owed money to the ATO and were charged interest, that interest was tax-deductible. From 1 July 2025, that’s no longer the case.

You’ll still be charged interest on unpaid or underpaid tax, but you won’t be able to claim it on your tax return—even if the amount is substantial.

However, in some situations, the ATO may still choose to remit (waive or reduce) these charges, especially where there are fair and reasonable circumstances behind the delay.

A Quick Explanation: GIC vs SIC

General Interest Charge (GIC)

Shortfall Interest Charge (SIC)

Once your assessment is amended, the GIC kicks in until the balance is cleared.

Why This Matters

If you’ve been treating the ATO like a flexible payment option for your tax obligations, this change makes that approach more expensive. Without the ability to deduct interest charges, your overall tax bill could be higher.

A Smarter Option: Consider Bank Finance

If you have ATO debt, it might be time to rethink how you manage it. One smart strategy is to speak to your bank or financial advisor about taking out a loan to cover the tax debt.

Why?

This change means the ATO will likely no longer be the cheapest option when managing cash flow.

What You Can Do Now

Useful References