The BAS Breakdown 2026: GST Adjustments, Errors and BAS Review

Learn how to review a BAS with confidence, spot common GST errors and adjustments, and know when a matter needs to be escalated.

In this session, we cover:

• GST adjustments vs errors in an earlier BAS

• Adjustment events: returned goods, cancellations and bad debts

• Changes in business or private use and in creditable purpose

• Know your client: understanding their business and the nexus

• Common errors: incorrect tax codes, duplicates, omitted sales and unsupported GST credits

• When to use the adjustment section of the BAS worksheet

• Reviewing sales, purchases, capital transactions and manual journals for GST risk

• Reconciling GST control accounts and investigating differences

• Documenting client queries, evidence and the basis for the GST treatment

• Escalating complex, unusual or material matters for technical review

• Practical application: act as the reviewer across a range of scenarios and make a call on each GST issue