ATO Compliance Calendar 2026 for All Australian SMEs

Quick Answer Australian SMEs in 2026 face quarterly BAS deadlines (28 days after quarter-end), monthly or quarterly Superannuation Guarantee payments shifting to payday super from 1 July 2026, annual income tax returns due 28 February or 31 October depending on lodgement method, FBT returns due 21 May, RDTI registration due 30 April for FY25 activities, and ASIC annual review payments due within two months of the company's review date. Missing any of these triggers automatic administrative penalties starting at $313 per 28-day period for individuals and scaling for entities.

The four compliance regimes every Australian SME runs simultaneously

Most owners think about compliance as "the BAS" and "the tax return." The reality is denser. Every Australian SME is running four parallel compliance programmes:

1. GST and BAS regime (ATO) — quarterly or monthly cycle

2. PAYG and superannuation regime (ATO) — monthly/quarterly cycle, shifting to payday from July 2026

3. Income tax regime (ATO) — annual cycle, complicated by RDTI and Division 7A overlays

4. Corporate compliance regime (ASIC) — annual review cycle plus event-driven filings

Here's the consolidated 2026 calendar with the deadlines that actually move money or trigger penalties.

Quarterly: BAS lodgement and payment

The Business Activity Statement is the most rhythmic compliance event in the Australian SME calendar. Standard quarterly BAS deadlines for 2026:

If you lodge through a registered tax or BAS agent, you generally get an extension of 4 weeks past these dates. If you lodge yourself, the dates above are firm. Late lodgement triggers Failure to Lodge (FTL) penalties starting at $313 per 28-day period and scaling with entity size.

Quarterly until 30 June 2026, then payday: Superannuation Guarantee

Until 30 June 2026, the standard quarterly SG payment dates apply:

Then everything changes on 1 July 2026. From that date, Superannuation Guarantee contributions must be paid on the same day as wages, with funds landing in employees' super accounts within seven business days. The current 12% Superannuation Guarantee rate applies. The ATO's free Small Business Superannuation Clearing House is being decommissioned on the same date.

This is the most operationally significant Australian SME compliance change of the decade. We've covered the cash-flow impact and readiness plan in Payday Super 2026: The cash-flow shock most Australian SMEs aren't ready for.

Annual: Income tax returns

Two main deadline tracks depending on how you lodge:

Self-lodgement:

• Individual and partnership returns: 31 October 2026 (for FY26 income year)

• Company returns: 28 February 2027 (for FY26 if lodging without an agent and not in Tax Agent program)

Lodgement through a registered tax agent: The tax agent lodgement program extends most deadlines materially — typically to 15 May 2027 for individuals, partnerships and trusts, and to 31 March 2027 or 15 May 2027 for companies depending on size. The exact date depends on your agent's lodgement profile.

Important: Companies with a non-standard substituted accounting period (SAP) or those identified by the ATO as "large" or "medium" entities have separate, earlier deadlines. Confirm yours with your tax agent at the start of the financial year, not the week before.

Annual: Fringe Benefits Tax (FBT)

The FBT year runs 1 April to 31 March. For FY26 (1 April 2025 – 31 March 2026):

• FBT return lodgement and payment due: 21 May 2026 (self-lodgement) or 25 June 2026 (tax agent lodgement)

Common SME FBT triggers: company cars used privately, novated leases, gym memberships, entertainment expenses, salary packaging arrangements. If you're providing any of these, run an FBT eligibility check before 31 March 2026 closes.

Annual: R&D Tax Incentive registration

For Australian companies claiming RDTI:

• AusIndustry registration deadline for FY25 R&D activities (year ended 30 June 2025): 30 April 2026

• AusIndustry registration deadline for FY26 R&D activities (year ending 30 June 2026): 30 April 2027

Registration with AusIndustry is a separate process from claiming the offset in the company tax return — both have to happen, in the right sequence, on time. We covered the documentation discipline that protects RDTI claims in The R&D Tax Incentive in 2026.

Variable: ASIC annual review

Every Australian company has an ASIC review date — usually the anniversary of incorporation. Within two months of that date each year:

• Confirm or update company details on ASIC records

• Pay the ASIC annual review fee ($321 for proprietary companies as of 2025–26)

• Pass a solvency resolution within two months of the review date

Late payment of the annual review fee triggers escalating late fees ($98 for up to 1 month late, $409 for more than 1 month late). Failure to pay can ultimately lead to deregistration.

Director ID — ongoing requirement

All directors of Australian companies must have a Director ID, applied for through the Australian Business Registry Services (ABRS). For new directors of new companies, the Director ID must be obtained before appointment. This is a permanent, one-per-person identifier — not a renewable item, but worth flagging because new directors and new entity additions trigger the requirement.

Single Touch Payroll (STP) — every payroll cycle

STP Phase 2 is now standard. Every payroll event must be reported to the ATO on or before the day employees are paid. Software handles this automatically if configured correctly. The compliance risk is configuration drift — when payroll software is set up wrong and STP submissions diverge from actual payroll, the ATO discovers it eventually and the reconciliation work is brutal.

State payroll tax — if you cross thresholds

Each state and territory has its own payroll tax threshold and rate:

If your wages bill crosses a state threshold, you must register for payroll tax in that state and lodge monthly or annual returns. Multi-state operators pay attention: the grouping rules can pull you above thresholds even when no single entity is.

The compliance calendar in one printable view

For Australian SME owners, the discipline that matters: pin a single calendar to the wall (or a Notion page, or an Asana board) with these recurring events:

Every 28 of the month following quarter-end: BAS lodgement deadline Every payroll cycle from 1 July 2026: Payday Super payment landing within 7 business days 31 March 2026: Last quarterly super deadline + FY26 FBT year-end 30 April 2026: AusIndustry RDTI registration for FY25 21 May 2026: FBT return lodgement (self-lodge) 1 July 2026: Payday Super begins; SBSCH closes; new financial year 31 October 2026: Individual income tax return (self-lodge) Anniversary of incorporation (variable): ASIC annual review

Miss any of these and the penalty starts running automatically. The ATO and ASIC both operate on real-time data now — there's no quiet period to catch up in.

Where this becomes a CFO conversation, not a bookkeeper one