Casual and Part-Time Worker Payroll in Australia 2026: Payday Super, STP Phase 2, and Bookkeeper Compliance

Managing payroll for casual and part-time workers is one of the most complex and error-prone tasks facing Australian employers and their bookkeepers in 2026. With the introduction of Payday Super from 1 July 2026, the ongoing requirements of Single Touch Payroll Phase 2, and the Fair Work Act's strict rules on casual loading and ordinary time earnings, getting payroll right for variable-hours workers has never been more consequential.

Understanding Casual and Part-Time Employment in Australia

Australian employment law draws a clear distinction between casual and part-time workers, and each classification carries different payroll obligations. Part-time employees work regular, predictable hours and receive the same entitlements as full-time employees on a pro-rata basis — including annual leave, personal leave, and notice periods.

Casual employees, by contrast, have no guaranteed hours and no expectation of ongoing work. In exchange, they receive a 25% casual loading on top of the applicable award or enterprise agreement rate. This loading compensates for the absence of paid leave entitlements. Since the Fair Work Amendment (Supporting Australia's Jobs and Economic Recovery) Act 2021, employers must also offer casual conversion to eligible employees after 12 months of regular and systematic engagement.

For bookkeepers, the critical distinction is that casual loading is not simply an add-on — it forms part of the employee's ordinary time earnings (OTE) for superannuation purposes, which has significant implications under Payday Super.

Superannuation on Casual Earnings: What Counts as OTE

One of the most common payroll errors bookkeepers encounter is the incorrect calculation of superannuation for casual employees. The Superannuation Guarantee (SG) rate is 12% of OTE, and for casual workers, OTE includes more than just the base hourly rate.

Under ATO guidance, OTE for casual employees includes:

• Base hourly rate — the award or agreement rate before loading
• Casual loading (25%) — this is explicitly included in OTE
• Shift loadings and penalty rates — Saturday, Sunday, and public holiday penalties are generally OTE
• Allowances that are part of ordinary pay — such as tool allowances paid regularly

Overtime payments are generally excluded from OTE. However, if a casual employee works what would be overtime hours for a full-time employee, the classification can become complex. Bookkeepers should refer to the relevant Modern Award and the ATO's Superannuation Guarantee Ruling SGR 2009/2 when in doubt.

Failing to include casual loading in the super calculation is a common cause of SG underpayment. Under Payday Super, these errors are now detected in near real-time, making accurate OTE calculation more urgent than ever.

Payday Super: New Obligations for Variable-Hours Workers

From 1 July 2026, all employers — regardless of size — must pay superannuation contributions with every pay run and ensure those contributions reach the employee's nominated fund within seven business days of the payday. This represents a fundamental shift from the previous quarterly payment model.

For casual and part-time workers, Payday Super creates several specific challenges:

• Frequent, small payments: Casual workers may be paid weekly or even daily in some industries. Each pay event triggers a separate super obligation, requiring a SuperStream-compliant clearing house capable of handling high-frequency, low-value transactions.
• New starters: For new casual employees, the first super contribution window is extended to 20 business days to allow time for fund nomination or stapling via the ATO's stapled fund service. After this initial period, the standard seven-day rule applies.
• Fund stapling: If a new casual employee does not nominate a fund, the employer must use the ATO's stapled fund service to identify their existing fund. Failure to do so and defaulting to the employer's default fund can result in compliance issues.
• SBSCH closure: The Small Business Superannuation Clearing House has closed. Employers previously relying on it must now use an alternative SuperStream-compliant clearing house, such as those offered by major payroll software providers.

Missing the seven-day deadline triggers the Superannuation Guarantee Charge (SGC), which includes the unpaid super, interest calculated from the payday, and an administration fee. Critically, the SGC is not tax-deductible, making late payments significantly more costly than timely ones.

STP Phase 2 Reporting for Casual and Part-Time Workers

Single Touch Payroll Phase 2 requires employers to disaggregate gross payments into specific income categories and report them to the ATO with every pay event. For casual and part-time workers, this granular reporting introduces several compliance requirements that bookkeepers must manage carefully.

Income Type and Tax Treatment Codes

Every STP Phase 2 report must include an income type code and a tax treatment code for each employee. For most casual and part-time workers, the income type is SAW (Salary and Wages). The tax treatment code is generated based on the employee's TFN declaration, residency status, and whether they have claimed the tax-free threshold.

Disaggregated Pay Categories

Bookkeepers must ensure their payroll software correctly maps each pay category to the appropriate STP Phase 2 reporting field. Common categories for casual workers include:

• Gross salary and wages — the base rate plus casual loading
• Allowances — reported separately by type (e.g., travel, tool, uniform)
• Overtime — reported separately and excluded from OTE for super purposes
• Paid leave — not applicable for casuals, but relevant for part-time workers
• Termination payments — if a casual engagement ends, any unused entitlements must be correctly classified

Incorrect mapping of pay categories is one of the most common STP Phase 2 errors. For example, classifying casual loading as an "allowance" rather than as part of gross wages can distort the ATO's income matching and trigger compliance queries.

Payslip Obligations

Under the Fair Work Act, employers must provide a compliant payslip within one working day of payday. For casual employees, the payslip must clearly show the base hourly rate, the casual loading as a separate line item, any penalty rates or allowances, and the superannuation contribution amount and fund details.

Common Payroll Mistakes for Casual and Part-Time Workers

Bookkeepers working with businesses that employ casual or part-time staff should be alert to the following frequent errors:

• Excluding casual loading from OTE: Calculating super on the base rate only, without including the 25% loading, results in systematic underpayment of superannuation.
• Incorrect award interpretation: Many Modern Awards have complex penalty rate structures. Applying the wrong rate for weekend, public holiday, or shift work can result in underpayment claims and Fair Work investigations.
• Missing the Payday Super deadline: Assuming the old quarterly model still applies and batching super payments monthly or quarterly will trigger SGC liability from 1 July 2026.
• Failing to use the stapled fund service: Not checking for a stapled fund for new casual starters and defaulting to the employer's fund can create compliance issues.
• Incorrect STP Phase 2 category mapping: Miscoding allowances, overtime, or casual loading in payroll software leads to inaccurate ATO reporting and potential data-matching discrepancies.
• Not reconciling STP reports: Failing to regularly reconcile payroll records against STP submissions means errors accumulate and are harder to correct at year-end.

Australian Regulatory Context

The regulatory framework governing casual and part-time payroll in Australia involves multiple agencies and pieces of legislation that bookkeepers must navigate.

The Australian Taxation Office (ATO) administers the Superannuation Guarantee, STP reporting, and PAYG withholding obligations. From 1 July 2026, the ATO receives real-time super liability data through STP and matches it against fund receipts via SuperStream, enabling near-instant detection of late or missing contributions.

The Fair Work Commission sets and updates Modern Award rates, including casual loadings and penalty rates. The National Employment Standards (NES) under the Fair Work Act 2009 establish minimum entitlements for all employees, including casual conversion rights.

The Tax Practitioners Board (TPB) regulates BAS agents, who are the only practitioners legally permitted to provide BAS and payroll tax agent services for a fee. Bookkeepers providing payroll services must hold a current BAS agent registration or work under the supervision of a registered agent.

The Office of the Fair Work Ombudsman investigates underpayment claims and can impose significant penalties on employers who fail to meet their obligations to casual and part-time workers. Wage theft laws in several states, including Victoria and Queensland, have elevated the consequences of payroll errors from civil to criminal liability in serious cases.

Practical Checklist for Bookkeepers

To maintain compliance when managing payroll for casual and part-time workers, bookkeepers should work through the following checklist for each client:

• Confirm employment classification: Verify whether each worker is genuinely casual or part-time, and document the basis for the classification.
• Identify the applicable Modern Award or enterprise agreement: Confirm the correct award coverage and applicable pay rates, including casual loading and penalty rates.
• Configure OTE correctly in payroll software: Ensure casual loading, shift loadings, and applicable allowances are included in the OTE calculation for superannuation.
• Set up a SuperStream-compliant clearing house: Confirm the clearing house can process frequent, small super payments and meets the seven-day Payday Super deadline.
• Check STP Phase 2 pay category mapping: Review all pay categories in the payroll software to ensure they map to the correct STP Phase 2 reporting fields.
• Implement a payslip compliance check: Verify that payslips are issued within one working day and include all required information for casual employees.
• Schedule regular reconciliations: Reconcile payroll records against STP submissions and super clearing house reports at least monthly.
• Review casual conversion obligations: Flag employees approaching 12 months of regular and systematic engagement for a casual conversion assessment.

How MyMoney® Can Help

Managing payroll for casual and part-time workers requires a bookkeeper who understands not just the mechanics of payroll software, but the complex interplay of award obligations, superannuation rules, and ATO reporting requirements. Getting it wrong can expose your business to SGC liability, Fair Work underpayment claims, and ATO data-matching queries.

MyMoney® connects Australian businesses with qualified, registered bookkeepers who specialise in payroll compliance for variable-hours workforces. Whether you need help configuring STP Phase 2, transitioning to Payday Super, or conducting a payroll audit, the right professional can protect your business and give you confidence that your obligations are being met.

Post a Brief on MyMoney® to describe your payroll needs and receive proposals from experienced bookkeepers. Or Browse Bookkeepers on MyMoney® to find a registered BAS agent with the expertise your business needs.