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Making adjustments on your BAS

How to make changes to current or past BAS to increase or decrease the amount of GST to be paid.

Last updated 14 September 2026

Found out about the meaning of and types of GST adjustments.

An adjustment event may occur on a sale or a purchase.

Work out what type of adjustment to follow.

Generally, you need a valid adjustment note before you can make a decreasing adjustment.

Work out how to make GST adjustments through different methods.

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