Four BAS deadlines per year. Miss one. Pay penalties per 28-day period.
28 October. 28 February. 28 April. 28 July. The four quarterly BAS deadlines that govern every Australian GST-registered business with under $20M turnover. Lodge electronically and you get four weeks more on three of them. Miss any deadline and the FTL penalty accrues per 28-day period.
Why this lives on XIntelliSync, not on a tax agent's website
BAS quarterly deadlines (28 Oct / 28 Feb / 28 Apr / 28 Jul) attract ATO Failure to Lodge penalties scaled by entity size — small entities $313+ per overdue quarter, large entities $1,565+, escalating with repeat offences. XIntelliSync's automated-tax-deadline-alerts agent surfaces the deadline 14 days, 7 days, and 24 hours before each quarter-end, with the prepared BAS bundle ready for ATO Business Portal upload. We don't lodge on your behalf — that's your tax agent's role or your direct portal action — but we make missing the deadline impossible to do silently. The article below is the deadline schedule, the FTL penalty matrix, and the 4-week tax-agent extension rules.
Quick answer
BAS quarterly deadlines: 28 October (Q1), 28 February (Q2), 28 April (Q3), 28 July (Q4). Lodging via the ATO Business Portal or via a registered tax agent grants a 4-week extension on Q1, Q3, and Q4 (no extension on Q2 because of the Christmas calendar). Monthly BAS is required above $20M annual turnover. Missing a deadline triggers Failure to Lodge penalties scaled by entity size and number of 28-day periods overdue.
The four quarters
Quarter by quarter. Self-lodgement vs tax-agent lodgement.
Quarterly BAS covers the previous three months. Self-lodgement deadlines are 28 days after each quarter end. Lodging via the ATO Business Portal or via a registered tax agent grants a 4-week extension on Q1, Q3, and Q4.
Self-lodgement deadline
28 October
Tax-agent / portal extension
25 November
Self-lodgement deadline 28 October. Lodging via the ATO Business Portal or via a registered tax agent grants a 4-week extension to 25 November.
Self-lodgement deadline
28 February
Tax-agent / portal extension
28 February
Q2 deadline aligned to 28 February for both self-lodgement and tax-agent lodgement (no separate extension because of the Christmas holiday calendar).
Self-lodgement deadline
28 April
Tax-agent / portal extension
26 May
Self-lodgement deadline 28 April. Tax-agent lodgement granted a 4-week extension to 26 May.
Self-lodgement deadline
28 July
Tax-agent / portal extension
25 August
Self-lodgement deadline 28 July. Tax-agent lodgement granted a 4-week extension to 25 August.
Failure to Lodge penalty schedule
Entity size. Penalty units per 28-day period.
The FTL penalty scales with entity size and the number of 28-day periods overdue. Penalty unit value is CPI-indexed; confirm current value at ato.gov.au.
Small entity
Annual turnover under $1M
1 penalty unit per 28-day period (max 5 units per BAS)
Maximum FTL penalty per overdue BAS scales with the current penalty unit value (CPI-indexed; confirm current value via ato.gov.au).
Medium entity
Annual turnover $1M to $20M
2 penalty units per 28-day period (max 10 units per BAS)
Doubled rate over small entity. Repeat lodgement failures attract escalating penalties.
Large entity
Annual turnover above $20M
5 penalty units per 28-day period (max 25 units per BAS)
Five-times rate. Large entities required to lodge BAS monthly (not quarterly) which compounds penalty exposure.
Significant global entity
Global parent turnover above $1B
Higher tier — penalty multiplier of up to 500x in extreme cases
Reserved for SGE classification. Most AU SMBs do not fall in this tier.
FTL penalty unit values verifiable on ato.gov.au/general/interest-and-penalties/penalties. GIC (general interest charge) on overdue tax accrues separately from FTL penalties.
Where to lodge externally
After XIntelliSync prepares. Before you confirm.
XIntelliSync is not a registered ATO Digital Service Provider and does not lodge on your behalf. Once XIntelliSync prepares your BAS, lodge externally at one of these official ATO portals:
ATO Business Portal — bp.ato.gov.au
For businesses with an ABN. Lodge BAS, STP Phase 2, TPAR, and other business activity reports. Requires myGovID + Relationship Authorisation Manager (RAM) access. 4-week lodgement extension applies on Q1, Q3, Q4 when lodging via this portal.
myGov — my.gov.au
For sole traders lodging BAS via personal ATO Online Services. Link your ATO account once via myGov to lodge individual BAS, STP, and access tax records.
Tax Practitioners Board — tpb.gov.au/tax-agent-finder
Find a registered Australian tax agent or BAS agent. Tax agents lodging on your behalf grant the same 4-week extension on Q1, Q3, Q4.
ATO BAS due-dates calendar — ato.gov.au
Official ATO BAS lodgement calendar with current and upcoming due dates. Source of truth for deadline confirmation.
All 22+ industries served
BAS cycle + GST treatment by industry.
Different industries have different GST classifications, different turnover thresholds, and different TPAR obligations. Below: the most-relevant BAS feature for every industry XIntelliSync serves.
Construction
TPAR mandatory — building & construction industry must report contractor payments annually by 28 August. GST on supplies, GST credits on materials. Progress claim invoicing creates BAS timing complexity.
Healthcare
Many medical services GST-free under Division 38-7 (medical services) and Division 38-10 (other health). Allied health may be partially GST-free. Pharmacy mixed — most prescription medicines GST-free, retail products taxable.
Hospitality
Restaurant meals consumed on-premises taxable at 10% GST. Takeaway food may be GST-free if it qualifies as basic food per Division 38. Liquor always taxable. Tip pooling does not affect GST.
Retail
Most retail goods 10% GST taxable. Basic food items (bread, milk, fresh fruit/veg, plain meat) GST-free under Division 38 Schedule 2. Mixed baskets require per-line classification — software with up-to-date ATO classification codes is essential.
Consulting / Professional Services
Most consulting services 10% GST taxable. Exports of services may be GST-free under Division 38. Sub-contracted work to other GST-registered consultants — GST on supplier invoice claimable as input credit. TPAR may apply for cleaning/IT/security services.
Digital / Tech
Software licences and SaaS subscriptions to AU customers: 10% GST. Exports to overseas customers: typically GST-free under Division 38 export rules. TPAR mandatory for IT services to other businesses. Stripe/payment-processor fees include GST claimable as input credit.
Finance
Most financial supplies INPUT-TAXED under Division 40 — no GST charged on supply, no GST credits claimable on related expenses. Fee-based services (advisory, brokerage) often taxable at 10% GST. Mixed-supply businesses must apportion input credits.
Legal
Legal services 10% GST taxable. Trust account holdings are NOT consideration for supply — no GST until earned/billed. Disbursements (court filing fees, expert reports) may be GST-free or taxable per ATO rulings. Expense recoveries treated per the Goods and Services Tax Ruling GSTR 2000/37.
Childcare
Childcare services GST-free under Division 38-145 if approved-services or registered-carer. CCS subsidy reconciliation creates BAS timing complexity. Materials and supplies (10% GST) claimable as input credits.
Education
Most education courses GST-free under Division 38-85 (education courses) when delivered by registered training organisations or approved tertiary providers. Course materials may be partially taxable. International student fees typically GST-free under Division 38 export rules.
Manufacturing
Manufacturing supplies generally 10% GST taxable. Exports GST-free under Division 38. Raw materials with GST claimable as input credits. Capital purchases (machinery, vehicles) GST claimable in the period acquired. Quarterly BAS most common; monthly required if turnover exceeds $20M.
Transport
Road freight services 10% GST taxable. International freight (export and import legs) typically GST-free under Division 38. Fuel tax credits available — separate claim through BAS. TPAR mandatory for road freight services to businesses.
Mining
Mining production 10% GST taxable; exports GST-free. Substantial fuel tax credits, R&D tax incentive offsets, and capital allowances flow through BAS. Native title and royalty payments have specific GST treatment per ATO mining-industry rulings.
Agriculture
Most fresh food (bread, milk, fruit, vegetables, meat) GST-free under Division 38 Schedule 2. Processed/packaged food typically taxable. Fuel tax credits available for off-road farm machinery. Livestock sales GST-free between primary producers.
Fitness
Fitness services 10% GST taxable. Membership fees GST applies. Equipment retail (apparel, supplements) taxable. Personal-trainer commissions to contractors may trigger TPAR if industry-wide reporting becomes mandatory.
Non-profit
Charitable not-for-profits with GST registration: most fundraising events GST-free under Division 38 if non-commercial test passes. Gifts and donations not consideration — no GST. Government grants may or may not be consideration depending on conditions. NDIS supports GST-free under Division 38-38.
Events
Event ticket sales 10% GST taxable. Bundled packages (ticket + food + accommodation) require apportionment per ATO events-industry guidance. Sponsorship income generally taxable. Door-takings reconciliation drives BAS-period accuracy.
Creative
Creative services to AU clients 10% GST taxable. International commissions GST-free under Division 38 export rules. Royalty income taxable. TPAR may apply for security/courier/cleaning sub-contractors used in production.
Marketing
Marketing services 10% GST taxable. Media spend pass-through (Google Ads, Meta Ads) — GST treatment depends on whether you re-bill or just facilitate. Overseas service exports GST-free under Division 38.
Human Resources
HR consulting and recruitment services 10% GST taxable. Placement fee payments are taxable supplies. Background-check pass-through costs require apportionment if charged at-cost vs marked-up.
Insurance
General insurance premiums INPUT-TAXED under Division 40 — no GST on the premium portion, but the policy holder may claim a decreasing adjustment. Life insurance premiums GST-free. Brokerage and intermediary services taxable at 10% GST.
Real Estate
Residential rent INPUT-TAXED under Division 40 — no GST charged, no GST credits on related expenses. Commercial property rent generally 10% GST taxable. Sale of new residential premises taxable; existing residential GST-free under Division 38. Property management fees 10% GST taxable.
BAS deadlines + FTL penalties. Questions answered.
When is BAS due each quarter?+
What's the difference between quarterly and monthly BAS lodgement?+
Do I get an automatic extension if I lodge electronically?+
What is the Failure to Lodge (FTL) penalty?+
Can I get an FTL penalty remitted?+
What happens if I owe GST and miss the BAS deadline?+
How does XIntelliSync prepare BAS to hit the deadline?+
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