Don't miss out this year: GST credits, fuel tax credits and your BAS

As 2026 kicks off, it’s a good time to make sure your business isn't missing out on valuable GST and fuel tax credits, and you’re not caught off guard by upcoming Business Activity Statement (BAS) deadlines.

GST credits

GST credits (input tax credits) are GST amounts you've paid on business purchases that you can get back, as long as you meet the requirements. If you buy something for your business and it includes GST, you can claim a credit on your BAS for that GST to reduce the amount owed to the ATO.

Only GST-registered businesses can claim GST credits, and you can only claim credits for goods or services used in running your business (not for personal expenses). The supplier must have charged you GST as part of the purchase price, and for purchases over $82.50 (including GST) you need a valid tax invoice.

Importantly, there's a time limit for claiming GST credits. Credits expire four years after the BAS due date for the period when you first could’ve claimed them. After that you miss out, so remember to review older expenses within the four-year window.

Fuel tax credits

Fuel tax credits are another way to put money back into your business. When your business uses eligible fuel in certain vehicles, machinery or equipment for work, you can claim a credit on your BAS for the fuel tax (excise) already built into the fuel price.

You need to register for fuel tax credits (as well as registering for GST). Fuel tax credit rates are indexed twice a year, and different activities have different rates.

Not all fuel use is eligible, and vehicle and machinery types matter. For example, fuel used in passenger cars or light vehicles on public roads doesn’t qualify for credits, because the government already reduces that excise with a road-user charge. 

Like GST credits, fuel tax credits have a four-year time limit. Eligibility expires four years after the BAS due date for the period when you could first have claimed the credits.

Your tax agent can help you assess whether fuel used in your business equipment or heavy vehicles is eligible for fuel tax credits, what rates apply, and whether you should claim by correcting a past BAS or including missed credits in your next BAS.

BAS dates

Staying on top of your BAS gives you peace of mind and helps you avoid late lodgment penalties, so start gathering invoices, receipts and other records now. Lodging early means you'll also get cash back sooner if you're due a refund.

Here are the key upcoming dates:

• 21 January: due date for monthly reporters to lodge and pay the December 2025 BAS. There’s an extension until 21 February 2026 for small businesses (turnover up to $10 million) lodging their BAS through a tax agent online.

• 28 January: deadline to make superannuation guarantee (SG) contributions for the October to December 2025 quarter. If your employees' super payments aren’t in their funds by this date, you'll have to lodge a superannuation guarantee charge statement and pay the SG charge, interest and admin fees.

• 28 February: due date for quarterly reporters to lodge and pay the October to December 2025 BAS. The one-month small business extension for the December quarter is already built into this date, so no further extensions are available.

Don't wait until the last minute to sort out credits or lodge returns. Starting the year right will save you headaches later, and you can unlock some business cash flow in the process.

Source: ATO - Miscellaneous Taxation Ruling; ATO - Act early: Protect your GST and fuel tax credit entitlements