Single Touch Payroll and IAS Reporting in Australia: A Guide for Employers

Author : Mehedi Hasan | Published On : 13 Oct 2026

Managing employees involves more than calculating wages and processing payments. Australian businesses must also understand payroll reporting, tax withholding, superannuation contributions and the activity statements required by the Australian Taxation Office (ATO).

Two important components of this process are Single Touch Payroll (STP) and Instalment Activity Statements (IAS).

Although both relate to business taxation and reporting, they serve different purposes. STP is primarily used to report payroll information, while an IAS may be used to report and pay certain PAYG obligations.

Understanding how these systems interact is important for employers, company directors and small business owners who want to maintain accurate records and meet their tax compliance responsibilities.

With the introduction of Payday Super from 1 July 2026, businesses must also pay closer attention to the timing of superannuation contributions and the accuracy of payroll information.

This guide explains how STP and IAS reporting work in Australia, their relationship with PAYG withholding, common reporting mistakes and practical ways to improve payroll compliance.

What Is the Difference Between Single Touch Payroll and IAS?

Single Touch Payroll is an Australian reporting system through which employers report relevant employee payroll information to the ATO using STP-enabled software. An Instalment Activity Statement is a tax document used to report and pay certain obligations, including PAYG withholding and PAYG instalments, where applicable.

The main difference is that STP reports payroll information, while an IAS supports reporting and payment of specified tax liabilities.

Both systems can apply to the same business.

For example, a company may report employee wages and PAYG withholding through STP each payday while separately reporting and paying PAYG withholding through an activity statement.

Understanding this distinction helps business owners avoid confusing the reporting of employee payments with the actual payment of tax liabilities.

What Is Single Touch Payroll (STP)?

Single Touch Payroll is an Australian Government reporting framework designed to streamline how employers report employee payroll information to the ATO.

Most employers must use STP-enabled payroll software or an approved reporting solution.

When an employer processes payroll, the relevant information is generally submitted electronically to the ATO.

What Information Is Reported Through STP?

Depending on the employee and applicable reporting rules, STP may include:

• Gross salary and wages

• PAYG withholding amounts

• Allowances and other relevant payments

• Certain deductions

• Salary sacrifice arrangements

• Relevant superannuation information

• Employment-related reporting details

The information reported through STP helps the ATO maintain records of employee income and withholding.

It also supports the information made available to employees through ATO online services.

Who Must Use STP?

Most Australian employers must report through Single Touch Payroll.

The requirements can apply to sole traders employing staff, companies, partnerships, trusts and other entities with employee reporting obligations.

Certain concessions or alternative reporting arrangements may be available in limited circumstances.

Businesses should confirm which rules apply to their employment arrangements.

How Does STP Reporting Work?

The general process involves:

1. Entering employee information into payroll software.

2. Calculating wages, withholding and relevant payroll amounts.

3. Processing employee payments.

4. Submitting the required payroll information through STP-enabled software.

5. Reviewing submission results and correcting errors where necessary.

Although software can automate much of the process, employers remain responsible for ensuring that the information is accurate.

What Is an Instalment Activity Statement (IAS)?

An Instalment Activity Statement is a reporting document issued by the ATO for certain taxation obligations.

It may be used where a taxpayer needs to report PAYG withholding, PAYG instalments or other applicable amounts outside their BAS reporting arrangements.

An IAS is not a substitute for payroll software and does not perform the same function as STP.

Who Needs to Lodge an IAS?

An IAS may be relevant to businesses or taxpayers that:

• Have PAYG withholding reporting obligations

• Need to report PAYG instalments

• Are not registered for GST but have relevant PAYG obligations

• Have reporting periods where certain liabilities are not included in a BAS

• Receive an IAS from the ATO under their reporting arrangements

The reporting requirements depend on the taxpayer's circumstances.

For example, a business registered for GST may report several obligations through its BAS rather than lodging a separate IAS for the same period.

Businesses should follow the activity statement arrangements established by the ATO.

What Information Appears on an IAS?

Depending on the form issued, an IAS may include information relating to:

• PAYG withholding

• PAYG instalments

• Relevant FBT instalments

• Other applicable reporting amounts

The exact labels and obligations vary according to the taxpayer's registration and reporting arrangements.

STP vs IAS vs BAS: Key Differences

STP, IAS and BAS are closely related to Australian business taxation, but they are not interchangeable.

Practical Example

Consider a Sydney-based consulting company employing five staff members.

The company processes payroll fortnightly and reports the relevant wages and PAYG withholding through STP.

It is also registered for GST and lodges quarterly BAS.

Its PAYG withholding obligations may be reported through the relevant activity statements according to its ATO reporting arrangements.

The business therefore needs accurate payroll records, STP reporting and activity statement reconciliations.

The fact that payroll information has been submitted through STP does not mean the related tax liability has automatically been paid.

Understanding PAYG Withholding in Australia

PAYG withholding is an important part of employer tax compliance.

Under the system, businesses withhold tax from certain payments and remit the withheld amounts to the ATO.

Which Payments May Require PAYG Withholding?

PAYG withholding can apply to:

• Employee salary and wages

• Payments to company directors and office holders

• Certain labour-hire payments

• Payments under voluntary agreements

• Certain payments where an Australian Business Number has not been quoted

• Other payments covered by withholding rules

The amount withheld depends on the payment type and applicable tax rules.

How Is PAYG Withholding Reported?

Employers generally report relevant payroll withholding information through STP.

The withholding liability must also be managed through the applicable activity statement and payment arrangements.

This distinction is important because reporting PAYG withholding through STP does not discharge the obligation to pay withheld amounts to the ATO.

What Happens if PAYG Withholding Is Incorrect?

Payroll errors can result in inaccurate withholding records and incorrect tax reporting.

Depending on the circumstances, businesses may need to:

• Review payroll calculations

• Correct STP information

• Reconcile withholding accounts

• Review activity statements

• Address underpaid tax liabilities

• Correct affected employee records

Some failures to comply with PAYG withholding requirements can also affect the deductibility of particular payments.

Businesses should investigate errors promptly and obtain professional advice where the correct treatment is uncertain.

PAYG Withholding vs PAYG Instalments

PAYG withholding and PAYG instalments are separate systems.

Despite similar names, they involve different obligations.

PAYG Withholding

PAYG withholding generally involves deducting tax from relevant payments made to employees and certain other recipients.

The withheld amount is remitted to the ATO on behalf of the recipient.

PAYG Instalments

PAYG instalments are payments towards a taxpayer's expected annual income tax liability.

Taxpayers generally enter the PAYG instalment system when they meet the relevant conditions.

These payments are credited against the final income tax assessment.

Why the Difference Matters

A company may have PAYG withholding obligations because it employs staff and PAYG instalment obligations because it earns business income.

Both liabilities can affect cash flow.

However, they should be recorded and reconciled separately.

Accounting software should distinguish employee withholding from instalments paid towards the company's own income tax.

When Must Australian Businesses Lodge IAS?

IAS lodgement and payment dates depend on the relevant reporting cycle and ATO arrangements.

Some taxpayers have monthly reporting obligations, while others report quarterly.

Monthly IAS Reporting

Monthly activity statements are generally due on the 21st day of the following month, subject to applicable concessions or variations.

For example, a monthly activity statement covering August would generally be due on 21 September.

Quarterly IAS Reporting

Quarterly activity statement due dates depend on the type of obligation and reporting arrangements.

Certain quarterly activity statements generally follow these due dates:

Different rules can apply to PAYG instalment notices, consolidated groups and registered agent lodgements.

The relevant date should always be confirmed from the taxpayer's ATO activity statement or instalment notice.

What if a Business Cannot Lodge on Time?

Business owners should contact the ATO or their registered tax practitioner as early as possible.

An extension or payment arrangement may be available in some circumstances.

However, businesses should not assume that an extension will automatically be granted.

STP Finalisation Requirements at the End of the Financial Year

Single Touch Payroll generally requires employers to complete an annual finalisation process.

This involves confirming that the relevant payroll information for employees has been reported for the financial year.

When Is STP Finalisation Due?

For most employers, the annual STP finalisation declaration is due by 14 July following the end of the financial year.

Different deadlines may apply to certain employment or reporting arrangements.

What Should Employers Review Before Finalising?

Before making the declaration, employers should review:

• Employee details

• Gross wages

• PAYG withholding

• Reportable allowances

• Salary sacrifice arrangements

• Relevant deductions

• Superannuation information

• Other reportable payroll amounts

Employers should also check that payroll records align with their accounting systems.

Why Is STP Finalisation Important?

STP finalisation informs the ATO that the employer has completed the relevant annual payroll reporting.

Accurate information supports employee income statements and tax return preparation.

Incorrect or incomplete finalisation can create complications for employees and require corrections.

Payday Super From 1 July 2026: What Employers Need to Know

Payday Super introduced major changes to Australian superannuation guarantee payment timing.

From 1 July 2026, employers generally need to make superannuation guarantee contributions at the same time they pay their employees, rather than following the previous quarterly contribution cycle.

How Does Payday Super Work?

Under the new framework, employers generally calculate superannuation guarantee contributions on qualifying earnings.

The superannuation guarantee rate for the 2026–27 financial year is 12%.

Qualifying earnings have a defined meaning under the new rules and may extend beyond traditional ordinary time earnings calculations.

Employers should ensure that their payroll systems apply the relevant requirements correctly.

Seven-Business-Day Receipt Requirement

Superannuation contributions generally must reach an employee's nominated superannuation fund within seven business days after payday.

Extended timeframes apply in certain circumstances, including some new employee arrangements.

It is important to distinguish initiating a payment from the fund actually receiving the contribution.

How Does Payday Super Affect Payroll?

Businesses may need to review:

• Payroll software settings

• Qualifying earnings calculations

• Superannuation payment processes

• Employee super fund details

• Payment processing times

• Superannuation reconciliations

• Payroll cash flow forecasting

What Happened to Quarterly Super Payments?

The previous quarterly superannuation guarantee payment arrangements generally applied to periods before 1 July 2026.

Employers still need to address outstanding obligations from earlier periods according to the rules that applied.

For example, the final quarterly contribution obligation for April–June 2026 generally required payment by 28 July 2026.

Employers should not confuse these historical obligations with the Payday Super requirements applying to paydays from 1 July 2026.

Why Superannuation Reconciliation Matters

Late or incorrect contributions may result in superannuation guarantee charge liabilities and other compliance consequences.

Maintaining accurate payroll and contribution records can help employers identify missed or incorrectly processed payments.

For current requirements, consult the ATO's Payday Super guidance.

Common STP and IAS Reporting Mistakes

Several payroll and activity statement errors can create unnecessary compliance problems.

Incorrect Employee Payroll Details

Errors in employee information, payment categories or withholding calculations can affect STP reporting.

Employers should review payroll records regularly and correct discrepancies promptly.

Confusing STP Reporting With PAYG Payment

Submitting STP information does not automatically remit withholding amounts to the ATO.

Businesses must separately manage applicable payment obligations.

Using Incorrect IAS Reporting Figures

Incorrect PAYG withholding or instalment figures can arise from incomplete records or a misunderstanding of reporting requirements.

Regular reconciliation can help identify discrepancies.

Missing Reporting Deadlines

Businesses may have different deadlines for payroll reporting, activity statements, annual finalisation and superannuation payments.

A central compliance calendar helps owners track these obligations.

Failing to Reconcile Payroll Accounts

Payroll liabilities recorded in accounting software may differ from amounts actually paid or reported.

Unreconciled balances can affect financial statements and tax information.

Overlooking Payday Super Requirements

Employers using outdated superannuation payment processes may fail to meet the requirements introduced from 1 July 2026.

Businesses should confirm that payroll software and payment arrangements support the new system.

How to Improve Payroll and Tax Reporting Compliance

A structured accounting process can make STP, IAS and PAYG obligations easier to manage.

Maintain Accurate Payroll Records

Employee records should include the relevant information required for wage calculations, withholding, superannuation and reporting.

Businesses should update these records whenever employee circumstances change.

Reconcile Payroll Regularly

Compare payroll reports with general ledger balances and payment records.

Investigate differences in wages, withholding and superannuation liabilities.

Review Activity Statement Obligations

Understand which taxes must be reported through BAS or IAS.

Check the business's registered reporting arrangements and relevant due dates.

Establish a Compliance Calendar

Create a calendar covering:

• Payroll processing dates

• STP submission requirements

• Superannuation contribution deadlines

• IAS and BAS reporting dates

• PAYG payment obligations

• Annual STP finalisation

• Business income tax return preparation

Review Accounting Software

Payroll and accounting software should be configured for the business's current circumstances and Australian regulatory requirements.

Software settings should be checked after legislative changes or changes to employee arrangements.

Seek Professional Accounting Support When Required

Businesses with multiple employees, complex structures or recurring reporting discrepancies may benefit from professional assistance.

An experienced accountant can help review payroll accounts, tax liabilities and financial reporting information.

When Should Businesses Engage an Accountant for STP and IAS Reporting?

Some businesses can manage routine payroll and activity statement processes internally.

Others may need professional support because their reporting arrangements are complex or their financial records require review.

Accounting assistance may be valuable when:

• PAYG withholding figures do not reconcile

• STP reports contain unresolved errors

• The business receives unexpected ATO notices

• Several reporting cycles or entities are involved

• Payroll liabilities are difficult to track

• IAS and BAS obligations overlap

• The business employs staff under different arrangements

• Superannuation reporting or payments require review

• Management needs more reliable financial information

Businesses dealing with multiple reporting obligations may benefit from professional business accounting and payroll tax reporting support covering STP, IAS, PAYG withholding, BAS and related financial records.

For business owners seeking a business accountant in Sydney, it can be useful to engage a firm that understands both ongoing business tax compliance and broader accounting requirements.

Before engaging an adviser, confirm their qualifications, registration and the services included in the proposed engagement.

Frequently Asked Questions About STP and IAS

What is the difference between STP and IAS?

STP is used to report relevant payroll information to the ATO, generally each time employees are paid. An IAS is used to report and pay certain tax obligations, such as PAYG withholding and PAYG instalments, according to the taxpayer's reporting arrangements.

Do businesses need both STP and IAS?

Some businesses may need both. Employers generally report relevant payroll information through STP and may also receive an IAS or BAS for their tax obligations. The correct arrangement depends on the business's registrations and reporting cycles.

Does STP replace BAS or IAS?

No. STP does not replace the need to report and pay applicable tax liabilities through the relevant activity statement or payment arrangements.

How often must employers report through STP?

Most employers report relevant payroll information through STP each time they process payroll. The applicable requirements depend on the employer's circumstances and any available concessions.

When is STP finalisation due?

Most employers must complete annual STP finalisation by 14 July after the end of the financial year, although different deadlines may apply in certain circumstances.

What is the difference between PAYG withholding and PAYG instalments?

PAYG withholding involves withholding tax from certain payments made to employees or other recipients. PAYG instalments are payments towards the taxpayer's own expected annual income tax liability.

How did Payday Super change employer obligations in 2026?

From 1 July 2026, employers generally must make superannuation guarantee contributions in connection with each payday, with contributions usually required to reach employees' superannuation funds within seven business days.

Can a business accountant help with STP and IAS compliance?

Yes. An appropriately qualified and registered accountant or tax practitioner can assist with relevant payroll reconciliations, PAYG reporting, activity statements and taxation advice within their authorised service scope.

Conclusion: Managing STP and IAS Reporting With Confidence

Single Touch Payroll and Instalment Activity Statements are important components of Australian business tax reporting.

Although both relate to taxation and financial information, they serve different purposes.

STP enables employers to report payroll information, while IAS and BAS arrangements support reporting and payment of relevant tax obligations.

Understanding these differences helps business owners maintain accurate records, manage PAYG liabilities and meet applicable reporting deadlines.

The introduction of Payday Super from 1 July 2026 has also made reliable payroll systems and timely superannuation payments increasingly important.

Employers should regularly review payroll records, reconcile tax liabilities and ensure their systems reflect current Australian reporting requirements.

Where financial records or tax obligations become complex, professional accounting support can help identify discrepancies and improve the reliability of business reporting.

Maintaining a consistent approach to payroll and tax compliance allows business owners to focus more effectively on running their businesses while understanding their financial responsibilities.

Disclaimer: This article provides general information only and does not consider your personal circumstances. Australian tax and superannuation rules may change. Seek advice from an appropriately qualified accountant, registered tax adviser or other relevant professional for guidance tailored to your business.