ATO GIC and SIC Rates by Quarter

What GIC and SIC are

The general interest charge (GIC) is what the ATO charges when a tax liability is not paid by its due date. It applies to income tax, GST, PAYG instalments, PAYG withholding and most other tax debts, and it keeps running until the balance is paid in full. A payment plan does not stop it.

The shortfall interest charge (SIC) applies instead when an assessment is amended upward and a shortfall appears. Because you usually could not have known about the shortfall until the amended assessment issued, SIC carries a smaller uplift than GIC. It runs from the original assessment's due date up to the day before the ATO gives notice of the amended assessment; after that, GIC applies to anything still unpaid past the new due date.

Both rates are set quarterly from the same base rate — the Reserve Bank's 90-day Bank Accepted Bill rate for the month before the quarter starts — with GIC adding 7 percentage points and SIC adding 3. That is why the GIC figure in the table below is always exactly 4 percentage points above the SIC figure for the same quarter.

How daily compounding works

The ATO does not charge the annual rate once a year. It converts the annual rate to a daily rate by dividing by the number of days in the calendar year, then applies that daily rate to the outstanding balance including interest already charged. Each day's charge therefore sits on a slightly larger balance than the day before.

In a leap year the divisor is 366 rather than 365, which is why the 2024 quarters in the table show a lower daily rate than a 2025 quarter with a similar annual percentage.

Worked example at the Jul-Sep 2026 rate: a $10,000.00 debt attracts $3.13 of GIC on the first day, and after 30 days the balance has grown to $10,094.37 — $94.37 of interest. Run your own dates through the ATO interest calculator, which uses the same quarterly table and handles part payments.

GIC compared with SIC

GIC and SIC are no longer deductible

From 1 July 2025, GIC and SIC are not deductible. Before that date they were generally deductible under section 8-1 of the ITAA 1997, which meant a taxpayer on the top marginal rate effectively carried well under half the headline cost.

The practical effect is that an ATO debt at 11.43% now costs the full 11.43%. Compare that against any commercial finance you are weighing up on a like-for-like, after-tax basis before deciding which debt to clear first.

Quarterly GIC and SIC rate table

Annual and daily rates exactly as published by the ATO, newest first, grouped by the financial year each quarter is filed under.

Daily rates are shown exactly as the ATO publishes them rather than re-derived from the rounded annual percentage.

Reducing what you pay

• Pay the balance down. Only payment stops GIC. A payment plan prevents firmer collection action but the charge keeps accruing on whatever is still outstanding.
• Lodge on time even if you cannot pay. Lodging late adds a failure to lodge penalty on top of GIC. Lodging on time and paying late only attracts GIC — use the failure to lodge penalty calculator to see what the difference is worth.
• Ask for remission. The ATO can remit GIC under section 8AAG where extraordinary circumstances, an ATO delay or ATO error contributed to the debt.
• Know the deadlines. The lodgment deadline reference shows when each obligation falls due.

Frequently asked questions