The short answer
A GST debt is GST your business has reported on its business activity statement but not paid to the ATO by the due date. It usually builds up when GST collected on sales is used for wages, suppliers or rent before the BAS falls due. GST debts carry more risk than many business owners realise. Unpaid GST is one of the three amounts, with PAYG withholding and the super guarantee charge, that can make company directors personally liable through a director penalty notice (ATO). The ATO can also estimate GST that hasn't been reported. The options are paying in full, an ATO payment plan, an interest-free plan for eligible small businesses or a loan that clears the debt. The general interest charge runs at 11.51% a year for October to December 2026, compounds daily and isn't tax-deductible. Lodge every BAS on time, even when you can't pay, because unreported amounts are treated more harshly.
How do GST debts build up?
GST is collected from customers throughout a quarter or month, but it's only paid to the ATO when the BAS is due. In the meantime it sits in the business account looking like working capital. A slow month, a big supplier bill or a customer paying late, and the money that was earmarked for GST goes elsewhere.
The accounting method matters too. A business on a non-cash, or accruals, basis owes GST on invoices issued during the period, even if customers haven't paid yet. That can create a GST bill before the cash arrives. Businesses with aggregated turnover under $10 million can generally choose to account for GST on a cash basis instead. Ask your accountant whether a switch would suit you.
Why is GST riskier for company directors?
Under the director penalty regime, directors can become personally liable for a company's unpaid GST, PAYG withholding and super guarantee charge. The ATO issues a director penalty notice, and can start recovering the penalty from the director 21 days later. If the company doesn't report on time, the ATO can estimate the unpaid GST, and estimated amounts are treated as never reported, which narrows the ways a director can get the penalty remitted.
That's why the first rule with a GST debt is to keep lodging. A BAS lodged on time with an unpaid balance leaves more options than one that isn't lodged at all. Our director penalty notice guide explains lockdown and non-lockdown notices.
What are your options for paying a GST debt?
| Option | Who it suits | Things to know |
|---|---|---|
| Pay in full | Businesses with the cash or a short timing gap | Stops interest straight away |
| Standard ATO payment plan | Most businesses owing up to $200,000 | Set up online or by phone. GIC keeps running and isn't deductible. |
| Interest-free payment plan | Small businesses that meet strict criteria | Turnover under $2 million, activity statement debts of $50,000 or less overdue up to 12 months, and unable to get finance through normal channels |
| Business loan to pay the ATO | Businesses that can borrow at a manageable cost | Clears the debt in one payment. Loan interest is generally deductible. |
| Property-backed loan | Larger debts or urgent deadlines | A caveat loan can settle within days |
Should you take a loan or an interest-free plan?
If your business qualifies for the ATO's interest-free plan, it's hard to beat on cost. The general interest charge is still applied, but remitted automatically while you keep to the plan. The catch is the eligibility list: annual turnover under $2 million, recent activity statement debts of $50,000 or less overdue for up to 12 months, a good payment and lodgement history, ongoing viability, and being unable to obtain finance through normal business channels. A business that can borrow may not qualify.
For everyone else, compare a standard plan with a loan. At the October to December 2026 rate of 11.51% compounding daily, a $60,000 GST debt carried for a year adds about $7,300 of non-deductible interest. Loan interest on a business tax debt is generally deductible, so the after-tax gap can be smaller than the headline rates suggest. Our GIC guide shows the comparison.
Will the ATO tell credit bureaus about a GST debt?
It can. The ATO may report a business's tax debt to registered credit reporting bureaus when at least $100,000 is overdue by more than 90 days and the business isn't engaging with the ATO, for example through a payment plan it's keeping. A reported tax debt shows up when lenders and suppliers run credit checks, so dealing with it early protects your access to finance.
How do you stop it happening again?
- Move one-eleventh of GST-inclusive sales to a separate account each week.
- Switch to monthly BAS so the bills are smaller and more frequent.
- Ask your accountant about cash-basis GST if slow-paying customers are the problem.
- Fix the underlying cash flow gap, which may call for a line of credit or invoice finance.
