The July–September Business Activity Statement is due on Wednesday 28 October 2026 if you lodge it yourself. A registered BAS or tax agent can take an eligible electronic lodgement out to 25 November 2026. Super guarantee for wages paid since 1 July is not on that calendar.
This is general information, not tax advice. The date on your own activity statement is the one that binds you.
What is actually due on 28 October
Three different obligations get talked about as if they were one bill. Only some of them land on this Wednesday.
BAS — yes, for quarterly reporters. You lodge quarterly when your GST turnover is under $20 million and the ATO has not told you to report monthly. The July, August and September quarter is due 28 October. The ATO's due-date page, updated 17 September 2026, is the source. Lodging online may earn an extra two weeks. That is "may", not a right you can assume.
PAYG instalments — yes, if you are on them. Quarterly instalment notices for the same July–September period are also due 28 October, including where the notice is GST only, PAYG only, or both. The amount is the one printed on the notice, not a percentage we can guess. The BAS calculator has a box for that figure (label T7) and adds it to net GST.
Super guarantee — no quarterly payment is due. Quarterly due dates applied to employee earnings paid up to 30 June 2026. The last of those was 28 July. From 1 July 2026, Payday Super replaced that rhythm. Super is calculated at 12% of qualifying earnings and has to be received by the fund, with enough information to allocate it, within 7 business days of payday, unless a longer exception applies (new employees are one). There is no super-guarantee amount calculator on this site. The contractor hourly rate calculator is the tool that prices super into what you charge.
Who it applies to
Sole traders. You lodge a BAS if you are registered for GST. Registration is compulsory once GST turnover reaches $75,000 ($150,000 for non-profits); taxi and rideshare drivers register from the first dollar. Below the threshold, registration is a choice, and once you have made it the lodgement obligation is real. You do not pay super guarantee on your own drawings. You do pay it, on the payday rules, if you have eligible employees — and some contractors count as employees for super even when they invoice you. If you are on PAYG instalments, that part of the statement is yours whether or not you are registered for GST.
Small businesses. Same BAS rules, plus wages. Wages are not GST. They go at W1, tax withheld at W2, and there is no GST credit on them. Super never appears on the BAS at all. If you account for GST on a cash basis — available under $10 million aggregated turnover — you enter what was actually received and paid in the quarter, not what was invoiced.
Employers. PAYG withholding for the quarter sits on the activity statement. Super sits in payroll: 12% of qualifying earnings, paid so the fund has it within seven business days of payday. The Small Business Superannuation Clearing House has closed, so a clearing house inside payroll software needs enough time to clear that window. State payroll tax is a third system again, with its own thresholds, and it is not part of the BAS.
Monthly BAS lodgers were already due on 21 October for September. This Wednesday is the quarterly date.
The arithmetic, matched to the calculator
The BAS calculator uses one worked quarter so the page and the tool agree. Sales of $33,000 including GST give label 1A of $3,000 ($33,000 ÷ 11). Purchases of $8,800 including GST give label 1B of $800. Net GST is $2,200. Add a PAYG instalment of $2,200 — that number comes from the notice, not from a formula — and the bill is $4,400. Divided by 13 weeks, that is $338 to move aside each week.
A price that already includes GST is divided by 11. A price that excludes GST is multiplied by 10%. Taking 10% of an inclusive amount overstates the GST. The GST calculator does either conversion on a single figure.
▶ How the $4,400 example is built
If the money is not there on Wednesday
Lodge anyway. Lodging and paying are separate, and a failure-to-lodge penalty attaches to the form, not to the cash.
For an individual or a small withholder the base penalty is one penalty unit for every 28 days or part of that the document is late, capped at five units. From 1 July 2026 a penalty unit is $364, so the base penalty runs from $364 to $1,820. The ATO says a penalty may be applied, and it looks at the circumstances. It is not a fine that prints itself at midnight. Medium withholders are charged twice the base, large withholders five times.
An amount still unpaid after the due date attracts the general interest charge. For October–December 2026 that rate is 11.51% a year, compounded daily (ATO GIC rates, updated 4 September 2026). GIC incurred from 1 July 2025 is not tax-deductible. The July–September quarter, which has just ended, was 11.43%.
The rest of the BAS year
| Quarter | Period | Self-lodger | BAS agent, electronic |
|---|---|---|---|
| Q1 ← this one | Jul–Sep 2026 | 28 October 2026 | 25 November 2026 |
| Q2 | Oct–Dec 2026 | 28 February 2027 | No further extension |
| Q3 | Jan–Mar 2027 | 28 April 2027 | 26 May 2027 |
| Q4 | Apr–Jun 2027 | 28 July 2027 | 25 August 2027, still to be confirmed |
Agent dates are from the BAS agent lodgment program 2026–27. Quarter 2 already includes the extra month, so an agent cannot push it past 28 February. The July BAS guide covers the quarter just gone, on the same arithmetic.
If you also lodge your own income tax return, that is a separate deadline: Monday 2 November, because 31 October is a Saturday. The self-lodger checklist is the page for that.