
ATO Interest Is No Longer Tax-Deductible: What GIC and SIC Now Really Cost Your Business
From 1 July 2025, the ATO's General Interest Charge and Shortfall Interest Charge are no longer tax-deductible — even on old tax debts. With GIC around 11% compounding daily, the after-tax cost of ATO debt jumped from roughly 7–8% to full sticker price. Here's how the incurred-date rule works and what to do about existing debt.










