BAS Statement in 2026: Due Dates, Labels, a Worked Example and How to Lodge

If you've registered for GST, the ATO will start sending you a BAS statement — a business activity statement — and from then on it becomes one of the fixed points in your calendar. This guide is for sole traders, company directors and bookkeepers who want to understand the form rather than just click through it. You'll see what each common label means (G1, 1A, 1B, W1, W2 and T7), which reporting cycle applies to you, the 2026-27 BAS due dates for self-lodgers, online lodgers and registered agents, a full worked quarter in Australian dollars, and what late lodgement or late payment actually costs.

Quick answer

A BAS is the ATO form a GST-registered business uses to report and pay GST, PAYG withholding from wages and PAYG instalments of income tax. Most small businesses lodge quarterly. The quarterly due dates are 28 October, 28 February, 28 April and 28 July; monthly BAS is due on the 21st of the next month. Lodge online yourself and you usually get 2 weeks more for quarters 1, 3 and 4; a registered agent can get later dates still.

• Simpler BAS (GST turnover under A$10 million): report just G1, 1A and 1B for GST

• Q1 2026-27: due 28 Oct 2026 · online 11 Nov 2026 · via agent 25 Nov 2026

• Q2 2026-27: due 28 Feb 2027 (a Sunday, so Monday 1 Mar) — no further extension

• Late lodgement: A$364 per 28 days, up to A$1,820 for small businesses

• Late payment: general interest charge at 11.51% a year, compounding daily (Oct–Dec 2026)

What a BAS statement is and who has to lodge one

A business activity statement is the ATO's all-in-one return for a business's regular tax obligations. Once you're registered for GST, the ATO issues you a BAS for each reporting period, and that statement is where you report the GST you charged, the GST credits you're claiming, the tax you withheld from your employees' pay and, if you're in the PAYG instalments system, a prepayment of your own income tax. Businesses with fuel tax credits, fringe benefits tax instalments, wine equalisation tax or luxury car tax report those on the same form.

The trigger is registration, not income. GST registration is compulsory once your GST turnover reaches A$75,000 (A$150,000 for not-for-profits), and you need an ABN before you can register. Some businesses below the threshold register voluntarily — for example, to claim GST credits on set-up costs — and they get a BAS too, though they may be able to report annually.

You can also receive an activity statement without being registered for GST. A business that employs staff and is registered for PAYG withholding, or a sole trader the ATO has entered into PAYG instalments, gets a statement for those obligations. For simplicity, people call all of these "the BAS", and this guide does too.

One rule catches many first-timers: once a BAS has been issued, you must lodge it, even if you made no sales and paid no wages. That is a nil BAS, covered below. If you've stopped trading, cancel your GST registration (and other roles) rather than lodging nil statements indefinitely — but only after every outstanding lodgment is up to date.

Monthly, quarterly or annual: which BAS cycle applies

How often you lodge depends mainly on your GST turnover — your business's total sales over 12 months, excluding GST and input-taxed sales. The ATO's due-dates page sets out three cycles, and the cycle decides your due dates.

Most small businesses are in the third row: quarterly Simpler BAS. Choosing monthly is allowed even if you're small. The ATO argues smaller, more frequent payments can help cash flow, and some owners like reconciling their books every month anyway. The trade-off is twelve lodgments a year instead of four, and monthly BAS gets neither the two-week online concession nor agent extensions (apart from one December concession described below).

There is also a newer reason a small business can end up on monthly BAS without asking. In March 2025 the ATO told about 3,500 businesses with a history of late or missed lodgment and payment that they would move from quarterly to monthly GST reporting from 1 April 2025, for at least 12 months. The ATO has said it will keep moving businesses with a poor compliance history to monthly reporting where appropriate. If you've had repeated late BAS, getting back on time is the best way to avoid that.

To change cycle voluntarily, companies and other entities (or their agent) use Online services for business: taxpayer profile, then tax registration, then Update. Sole traders phone the ATO or write in. If you ask early in a period, the change usually starts straight away; later requests take effect from the next quarter or year, and you generally can't change again within 12 months.

The BAS labels explained: G1, 1A, 1B, W1, W2 and T7

The labels on your BAS depend on what you're registered for, so your form may show more or fewer boxes than a colleague's. Here are the ones most small businesses meet.

GST labels

G1 — Total sales. Everything you sold during the period, including GST, along with GST-free and export sales. It's a gross figure. If you account for GST on a cash basis, G1 is what you were paid in the period; on a non-cash (accruals) basis, it's what you invoiced.

1A — GST on sales. The GST you charged. For taxable sales it's one-eleventh of the GST-inclusive amount — on a A$1,100 sale, A$100. Our GST guide works through the formulas.

1B — GST on purchases. The GST credits you can claim on business purchases, again usually one-eleventh of the GST-inclusive price, provided you hold a valid tax invoice where one is required (for purchases over A$82.50 including GST).

Under Simpler BAS, which applies when your GST turnover is under A$10 million, those three are the only GST labels you complete. Businesses on full reporting also complete G2 (export sales), G3 (other GST-free sales), G10 (capital purchases) and G11 (non-capital purchases), and may use the calculation worksheet method. If you have wine equalisation tax, luxury car tax or fuel tax credits, labels such as 1C, 1D, 7C and 7D appear on your form as well.

PAYG withholding labels

If you pay employees or directors, the ATO's PAYG withholding instructions cover these labels:

W1 — Total salary, wages and other payments. Gross wages, directors' fees, leave loading, termination payments and similar amounts you'd normally withhold from — even if you didn't withhold anything because the amount was under the tax-free threshold. Salary-sacrificed amounts and super contributions stay out.

W2 — Amounts withheld from the payments at W1. The tax you took out of those wages. If you use Single Touch Payroll, W1 and W2 are usually pre-filled from your STP data, so check them against your payroll reports rather than re-keying them.

W4 — Amounts withheld where no ABN is quoted. If a supplier invoiced you without an ABN, you must withhold 47% of the invoice and report it here — a good reason to check every supplier's ABN before you pay (see our ABN lookup guide). W3 covers other withholding, such as investment income paid without a TFN.

W5 — Total amounts withheld (W2 + W4 + W3), which you copy to label 4 in the summary. Large withholders, who pay electronically within days of each payday, complete only W1. For how the tax at W2 is worked out, see our PAYG withholding guide.

PAYG instalment labels

If the ATO has put you into PAYG instalments, your first BAS of the year may offer two options. Option 1 shows an instalment amount the ATO has calculated at T7; you pay that amount, or vary it using T8 (estimated tax for the year), T9 (varied amount) and T4 (reason code). Option 2 asks you to report your instalment income at T1 — broadly your gross business and investment income excluding GST — and multiply it by the instalment rate at T2 (or a varied rate at T3). Either way, the result goes to 5A in the summary. If you only have instalments and don't vary the amount, you can simply pay the instalment notice without lodging it.

The summary section

The back page pulls everything together. 8A is the total you owe — typically 1A + 4 + 5A, plus any other liabilities. 8B is what the ATO owes you — typically 1B, plus any credits such as 5B. 9 is the difference: a payment if 8A is larger, a refund if 8B is larger. Report whole dollars only and round cents down.

BAS due dates for 2026-27

The standard dates don't change from year to year, but which day of the week they fall on does, and that matters. If a due date lands on a weekend or public holiday, you have until the next business day to lodge and pay.

Quarterly BAS due dates 2026-27 — by how you lodge

Quarter	Standard (paper or self)	Lodged online yourself	Via a registered agent
Q4 2025-26 (Apr–Jun 2026)	28 July 2026	11 August 2026	25 August 2026
Q1 2026-27 (Jul–Sep 2026)	28 October 2026	11 November 2026	25 November 2026
Q2 2026-27 (Oct–Dec 2026)	28 February 2027 (Sun → Mon 1 March)	No extension	No extension
Q3 2026-27 (Jan–Mar 2027)	28 April 2027	12 May 2027	26 May 2027
Q4 2026-27 (Apr–Jun 2027)	28 July 2027	11 August 2027	25 August 2027 (to be confirmed)

Q4 2025-26 (Apr–Jun 2026)

Standard (paper or self)

28 July 2026

Lodged online yourself

11 August 2026

Via a registered agent

25 August 2026

Q1 2026-27 (Jul–Sep 2026)

Standard (paper or self)

28 October 2026

Lodged online yourself

11 November 2026

Via a registered agent

25 November 2026

Q2 2026-27 (Oct–Dec 2026)

Standard (paper or self)

28 February 2027 (Sun → Mon 1 March)

Lodged online yourself

No extension

Via a registered agent

No extension

Q3 2026-27 (Jan–Mar 2027)

Standard (paper or self)

28 April 2027

Lodged online yourself

12 May 2027

Via a registered agent

26 May 2027

Q4 2026-27 (Apr–Jun 2027)

Standard (paper or self)

28 July 2027

Lodged online yourself

11 August 2027

Via a registered agent

25 August 2027 (to be confirmed)

The online two-week concession

The ATO gives an extra 2 weeks to lodge and pay quarterly BAS for quarters 1, 3 and 4 if you receive and lodge them online — through Online services for business, Online services for individuals and sole traders via myGov, or business software that lodges through Standard Business Reporting. You don't apply; the later date simply appears on the statement once it's issued. It doesn't apply to quarter 2, which already carries a built-in one-month extension, to monthly BAS, to instalment notices (forms R, S and T) or to large business clients.

Registered agent dates

A registered tax or BAS agent who lodges electronically can use the ATO's registered agent lodgment program. For 2026-27, eligible quarterly statements are due on 25 November 2026, 26 May 2027 and 25 August 2027 (the last to be confirmed when the 2027-28 program is published). The catch is eligibility: the extra time applies only to statements that generate after your previous BAS was lodged electronically, so a brand-new client's first BAS, or a business that last lodged on paper, may face the earlier date. Statements with monthly PAYG instalments or a monthly GST cycle aren't eligible, and nor are businesses whose quarters don't line up with the standard ones. Agents can confirm a client's actual due date in Online services for agents.

Monthly and annual due dates

Monthly BAS is due on the 21st of the following month — a July BAS is due 21 August. In 2026-27, watch for weekends: the October 2026 BAS falls due on Saturday 21 November, so you have until Monday 23 November. The December monthly BAS has a concession: businesses with turnover up to A$10 million that report GST monthly and lodge electronically have until 21 February (in 2027 a Sunday, so Monday 22 February), unless they're registered for deferred GST.

Annual GST returns for voluntary registrants are due on 31 October — in 2026 a Saturday, so Monday 2 November — or 28 February if you don't have to lodge an income tax return. If you're on GST instalments, the annual return is due with your tax return, and your quarterly instalments follow the normal quarterly dates.

A worked quarterly BAS (July–September 2026)

Here's a realistic example of a quarterly BAS statement. Priya runs a small café in Parramatta as a company. Her GST turnover is about A$260,000, so she's on quarterly Simpler BAS, uses the cash basis, has two part-time staff and is in PAYG instalments with an ATO-calculated amount. Her figures for the July–September 2026 quarter are:

• Takings through the till and EFTPOS: A$66,000 including GST. Of that, A$5,500 is GST-free (packaged bread and milk sold as groceries); the remaining A$60,500 is taxable.
• Taxable business purchases with valid tax invoices: A$27,500 including GST (coffee beans, takeaway packaging, rent, electricity, a new grinder).
• Gross wages paid: A$24,000, with A$3,100 withheld and reported through STP.
• ATO instalment amount shown at T7: A$1,200.

Filling in Priya's BAS, label by label

1. 1

   G1 — total sales: A$66,000

   All sales including GST, and including the A$5,500 of GST-free groceries. Simpler BAS doesn't ask her to split them out.

2. 2

   1A — GST on sales: A$5,500

   Only the taxable part carries GST: A$60,500 ÷ 11 = A$5,500.

3. 3

   1B — GST on purchases: A$2,500

   A$27,500 ÷ 11 = A$2,500 in GST credits, backed by tax invoices.

   Tip: Purchases from suppliers who aren't registered for GST carry no GST — leave them out of 1B even though they're a business cost.

4. 4

   W1 A$24,000 · W2 A$3,100 → label 4: A$3,100

   Pre-filled from Single Touch Payroll; she checks them against her payroll report for the quarter.

5. 5

   T7 A$1,200 → label 5A: A$1,200

   She accepts the ATO's instalment amount rather than varying it.

6. 6

   8A A$9,800 · 8B A$2,500 · 9 = A$7,300 to pay

   8A = 5,500 + 3,100 + 1,200. 8B = 2,500. The difference is her payment, due 28 October 2026 — or 11 November 2026 if she lodges online herself.

The total looks large next to her profit for the quarter, but most of it was never hers: A$5,500 is GST customers paid on top of her prices, and A$3,100 is her staff's income tax. Only the A$1,200 instalment is her company's own tax, and that will be credited when the company lodges its return. Many small business owners move one-eleventh of each day's taxable takings and each payday's withholding into a separate account so the BAS bill is never a surprise.

If Priya pays two weeks after her online due date, interest accrues from the due date. On A$7,300 at the October–December 2026 GIC rate, 30 days late adds roughly A$69 — not ruinous, but it compounds daily and keeps growing.

How to lodge and pay your BAS

The ATO offers three ways to lodge.

Online yourself. Companies, trusts and partnerships use Online services for business, which needs a Digital ID such as myID. Sole traders can also use Online services for individuals and sole traders through a myGov account linked to the ATO. Many businesses lodge straight from accounting software that supports Standard Business Reporting. The ATO says statements generally appear in online services about a week after they're generated, and most people get an email around 21 days before the due date. Lodging online gives you the two-week concession on eligible quarters, error alerts, and usually faster refunds. Businesses with GST turnover of A$20 million or more must lodge online.

Through a registered tax or BAS agent. An agent can prepare, lodge, revise and pay on your behalf through Online services for agents or practice software, and you keep your own online access to see what's been lodged. Check an agent's registration on the Tax Practitioners Board register before you hand over access. Besides the later lodgment program dates, an agent's main value is getting the classification of sales and purchases right — the usual source of BAS errors.

On paper. If you still lodge by mail, the ATO sends a personalised form; you can't use a sample BAS because each form is unique to you. Paper statements can take up to three weeks to arrive and don't get the online concession. Use a black pen, leave non-applicable boxes blank, write whole dollars only and don't use symbols.

From books to lodged BAS

Step 1

Reconcile bank & sales

Step 2

Check tax invoices for 1B

Step 3

Confirm STP totals (W1, W2)

Step 4

Review T7 or calculate T1 × T2

Step 5

Lodge

online, agent or paper

Step 6

Pay using your PRN

by the due date

Payment is separate from lodgment but due on the same day. You'll need your payment reference number (PRN) for BPAY or bank transfer; the ATO's "How to pay" page lists the current options. You can pay early, and extra credit sits on your account to offset the next liability.

Lodging a nil BAS

If you had no sales, purchases, wages or instalments in the period, you still lodge — as nil. Online, open the statement, choose Prepare and then Prepare as nil. You can also use the ATO's automated phone service on 13 72 26, any time, for up to three current or overdue statements at once; have your ABN or TFN and the BAS document ID ready. The phone option isn't available for annual GST returns, GST instalment payers, or a statement with a pre-printed amount above zero at labels such as T7 or F1.

Penalties, interest and what to do if you can't pay

There are two separate costs for getting a BAS wrong on timing: one for lodging late and one for paying late.

Failure-to-lodge (FTL) penalty. The ATO can charge one penalty unit for each 28 days (or part) a BAS is overdue, up to five penalty units. The penalty unit rose to A$364 for infringements from 1 July 2026 (it was A$330), so a small business that is more than 112 days late can face A$1,820 per statement. The base is doubled for medium withholders and multiplied by five for large withholders. In practice the ATO says it doesn't generally penalise isolated late lodgments, it usually warns you first, and it generally won't issue an FTL penalty for a late BAS that results in a nil amount or a refund (unless you're a large withholder or the penalty was already applied). You can ask for remission, but you'll be expected to lodge everything outstanding first.

General interest charge (GIC). Any amount not paid by the due date attracts GIC, calculated daily on a compounding basis. The rate is reset every quarter: 11.51% a year for October–December 2026, up from 10.61% a year earlier. Since 1 July 2025, GIC is no longer tax-deductible, which makes paying late noticeably more expensive than it used to be. You can request remission if there were circumstances outside your control.

If you can't pay in full, lodge on time anyway — lodging stops the FTL penalty clock even if payment follows later, and it shows the ATO the true figure. Then contact the ATO or your agent before the due date. If you owe A$200,000 or less, you can generally set up a payment plan yourself in online services; plans need an up-front payment and GIC keeps accruing on the balance, so a shorter plan costs less. Businesses affected by a declared natural disaster may get extra time.

Common BAS mistakes and how to fix them

Most BAS problems come from a handful of habits.

The ATO distinguishes a mistake — an amount that was wrong when you lodged — from an adjustment, where something later changes a correct amount, such as a refund to a customer or a price change. Adjustments go in the BAS for the period you become aware of them. Many GST mistakes can be corrected in your next BAS, subject to time and value limits; if yours can't, you lodge a revision of the original statement online, through your agent, or with a paper revision form by phoning 13 28 66. Payroll errors that flow from STP corrections can often be carried forward into the current period's PAYG withholding.

Official ATO links

• Due dates for lodging and paying your BAS
• Two-week online lodgment concession
• Registered agent lodgment program — activity statements2026-27 agent due dates
• How to lodge your BAS (incl. nil BAS)
• Quarterly GST reporting and Simpler BAS
• PAYG withholding labels (W1–W5)
• General interest charge rates

What to do next

Put the due dates for your cycle into your calendar now, with the right column — standard, online or agent — and add a reminder a week earlier to reconcile. If you're still working out GST on individual sales, use our Australia GST calculator, and read the GST guide for what is taxable, GST-free or input-taxed. If you're about to hire, the PAYG withholding guide explains the W2 figure. And before claiming any GST credit from a new supplier, run a quick ABN lookup to confirm they're registered for GST.

This is general information, not legal or tax advice — confirm on the official source or with a professional.

Frequently asked questions

When are BAS statements due in 2026-27?

Quarterly BAS is due on 28 October 2026 (July–September), 28 February 2027 (October–December — it falls on a Sunday, so 1 March 2027), 28 April 2027 (January–March) and 28 July 2027 (April–June). Monthly BAS is due on the 21st of the next month. Lodging online yourself adds 2 weeks to quarters 1, 3 and 4; a registered agent can get later dates.

What is a BAS statement?

A business activity statement (BAS) is the form a GST-registered business lodges with the ATO to report and pay GST, PAYG withholding from wages, PAYG income tax instalments and some other taxes such as fuel tax credits. It is issued for each reporting period — monthly, quarterly or annually — and you lodge it even when you have nothing to report.

Do I have to lodge a BAS if I had no sales?

Yes. If a BAS has been issued to you, you lodge it by the due date even with nothing to report — as a 'nil' BAS. Online, choose Prepare as nil. You can also lodge a nil BAS through the ATO's automated phone service on 13 72 26, for up to three statements at a time, as long as no pre-printed amount sits at labels such as T7.

What happens if I lodge my BAS late?

The ATO can apply a failure-to-lodge penalty of one penalty unit (A$364 from 1 July 2026) for every 28 days late, up to five units (A$1,820) for small businesses, doubled or multiplied by five for bigger withholders. Unpaid amounts also attract general interest charge, currently 11.51% a year compounding daily. Penalties usually aren't applied to nil or refund BAS.

What do G1, 1A and 1B mean on a BAS?

G1 is your total sales for the period, including GST. 1A is the GST you collected on those sales, and 1B is the GST credits you can claim on business purchases. Businesses with GST turnover under A$10 million use Simpler BAS and only report these three GST labels; larger businesses also report export, GST-free and purchase labels.

How much extra time does a BAS agent get?

Under the ATO's 2026-27 registered agent lodgment program, eligible quarterly BAS lodged electronically by an agent are due on 25 November 2026 (quarter 1), 26 May 2027 (quarter 3) and 25 August 2027 (quarter 4, to be confirmed). There is no agent extension for quarter 2, which is already due on 28 February. Monthly BAS gets no agent extension.

Sources & verification

Figures on this page were checked against the sources below when it was last reviewed on 7 October 2026. Each rate and limit is stored once with its own official source and review date, and official update channels are monitored daily so changes are picked up. How we verify

1. 1.Due dates for lodging and paying your BAS — Australian Taxation Office · accessed 7 October 2026
2. 2.Two week lodgment concession – terms and conditions — Australian Taxation Office · accessed 7 October 2026
3. 3.Registered agent lodgment program — activity statements — Australian Taxation Office · accessed 7 October 2026
4. 4.How to lodge your BAS — Australian Taxation Office · accessed 7 October 2026
5. 5.Quarterly GST reporting — Australian Taxation Office · accessed 7 October 2026
6. 6.Pay as you go (PAYG) withholding — completing your activity statement — Australian Taxation Office · accessed 7 October 2026
7. 7.PAYG instalments – how to complete your activity statement — Australian Taxation Office · accessed 7 October 2026
8. 8.Failure to lodge on time penalty — Australian Taxation Office · accessed 7 October 2026
9. 9.Penalty units — Australian Taxation Office · accessed 7 October 2026
10. 10.General interest charge (GIC) rates — Australian Taxation Office · accessed 7 October 2026
11. 11.General interest charge — Australian Taxation Office · accessed 7 October 2026
12. 12.Fixing BAS mistakes or making adjustments — Australian Taxation Office · accessed 7 October 2026
13. 13.Quarterly to monthly GST reporting — Australian Taxation Office · accessed 7 October 2026