Keeping track of BAS due dates is critical for Australian businesses. Late lodgement attracts penalties from the ATO, and late payment incurs interest charges. Whether you lodge quarterly or monthly, knowing your deadlines and planning ahead prevents costly mistakes and cash flow surprises.
Determine your BAS lodgement frequency (monthly or quarterly)
Mark all due dates in your calendar at the start of the financial year
Set reminders 2 weeks before each due date to start reconciliation
Complete bank reconciliation at least 1 week before the due date
Generate and review BAS report 3-5 days before the deadline
Lodge on time via the ATO portal, myGov or tax agent
Set aside funds for the payment well before the due date
Keep records of lodgement confirmation for your files
Businesses in Australia operating under the GST + BAS system must meet these compliance requirements set by ATO:
Confusing lodgement dates with payment dates
Not knowing that tax agents may have different due dates
Forgetting that the December quarter BAS has an extended deadline to 28 February
Not factoring in public holidays that may shift due dates
Assuming an accountant has lodged without confirming
Waiting until the last day to start preparing the BAS
SortBooks connects to your Xero account and handles GST + BAS compliance automatically. Every transaction is categorised with the correct tax treatment, bank feeds are reconciled in real-time and your ATO-ready reports are always up to date. No more last-minute scrambles or manual data entry.
Every transaction gets the correct GST + BAS code automatically - 97%+ accuracy from day one.
Generate compliant reports for ATO at any time - no reconciliation needed.
Never miss a filing deadline. SortBooks tracks your obligations and reminds you in advance.
Q1 (July-September 2025): due 28 October 2025. Q2 (October-December 2025): due 28 February 2026. Q3 (January-March 2026): due 28 April 2026. Q4 (April-June 2026): due 28 July 2026.
The ATO imposes a Failure to Lodge (FTL) penalty of one penalty unit ($313 in 2025-26) for each 28-day period the BAS is overdue, up to a maximum of 5 penalty units. Interest also accrues on any unpaid tax amount.
SortBooks keeps your books reconciled in real-time, so there is no last-minute rush. It sends deadline reminders and your BAS report is always ready to review - making on-time lodgement effortless.
Join thousands of Australia businesses using AI to handle their bookkeeping and tax compliance.