GST & BAS · AU

BAS (Business Activity Statement)

The form GST-registered businesses use to report GST and PAYG.

A BAS is the form you lodge with the ATO — usually each quarter — to report the GST you collected, the GST you’re claiming back, and any PAYG amounts. The difference between GST collected (1A) and GST paid (1B) is what you pay or get refunded.

Most small businesses lodge a BAS quarterly, due about four weeks after the quarter ends. Keeping GST sorted through the year makes each BAS a few taps instead of a scramble.

Worked example

Over a quarter you invoice $33,000 including GST, so GST collected (1A) is $3,000. You spent $11,000 including GST on supplies, so GST paid (1B) is $1,000. Your BAS shows $3,000 − $1,000 = $2,000 payable.

Common mistake

Claiming GST back on a purchase from a supplier who isn’t GST-registered. If there’s no GST on the invoice, there’s nothing to claim — which is exactly why a valid tax invoice matters.

Try the bas calculator

Grounded in ATO guidance. Figures last checked . General information, not tax advice.

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