Australian payroll is not a currency setting and a tax slab — it is a reporting obligation. Every pay run must be reported to the ATO on or before payday under Single Touch Payroll Phase 2, with income disaggregated into gross, paid leave, allowances by type, overtime, bonuses and commissions, directors' fees, salary sacrifice and lump sums, each carrying its own STP category. Superannuation guarantee accrues on ordinary time earnings — a definition that does not match "total gross" for most award-covered workforces — and under the payday-super reform contributions must reach the fund within days of payday rather than sitting in a quarterly pile. ERPNext core gives you Salary Structure, Salary Component, Payroll Entry and Salary Slip, plus generic leave and a payroll payable entry, but it has no concept of an STP income type, no OTE flag on a salary component, no super fund or stapling record, no ATO-shaped pay event, and no ABA bank file. Teams end up maintaining a spreadsheet beside ERPNext and re-keying numbers into an external lodgement tool, which is exactly where the errors and the late lodgements come from.

We build a proper Frappe app — a real app in apps/ with its own module, fixtures and hooks.py, not a pile of custom fields typed into production. The app adds an AU Payroll Settings single DocType (ABN, branch code, SG rate schedule with effective dates, maximum contribution base, default fund, ABA header details), extends Salary Component with STP Phase 2 classification fields (income type, disaggregation category, OTE-eligible flag, salary-sacrifice type, RESC and reportable-fringe-benefit handling), and adds an AU Employee Tax Details DocType per employee for TFN declaration data, residency, tax-free threshold, STSL/HELP debt, medicare levy variation and working-holiday-maker status. PAYG withholding is computed from ATO withholding coefficients held in a versioned AU Tax Scale DocType with a child table of thresholds, so a new financial year is a fixture import rather than a code change. A doc_events hook on Salary Slip validate re-derives OTE, super guarantee (with the SG rate resolved from the pay period's payment date, not today's date), STSL and PAYG, and blocks submission if any component is missing its STP classification.

Reporting is built as first-class documents rather than a report button. An STP Submission DocType is created from a Payroll Entry, assembles the pay-event payload with year-to-date figures per employee and per income stream, validates it against the schema before anything leaves the system, and stores the gateway response, receipt id and any error codes on the document — so a rejected lodgement is a record you reopen and resubmit, not a lost HTTP call. Submit events, update events and full-file replacements are separate submission types with their own state machine. Transmission runs as a background job on the Frappe queue with an idempotency key, so a slow gateway never blocks the payroll clerk and a timeout never double-lodges. A daily scheduler_events job flags any submitted pay run with no accepted pay event. Superannuation produces a Super Contribution Batch grouped by fund and USI for your clearing-house or SuperStream gateway, with a payday-super ageing view counting days from each payment date and alerts as the remittance window closes. Payments export as ABA files with BSB and account validation, correct lodgement reference and a balancing self-record, and employee income statements are produced for the financial year. Everything is reachable through whitelisted methods on the Frappe REST API — run_pay_event, get_super_liability, generate_aba, get_stp_status — and permissions ship as role profiles (AU Payroll Officer, AU Payroll Approver, Super Administrator) so a clerk can prepare a lodgement while only an approver can transmit it.

This is a build-to-order product, not a marketplace download. After a scoping call we confirm your awards and pay-item mapping, your entity structure (single ABN or several, with branch codes), your super clearing-house or SBR-enabled gateway, your bank's ABA dialect and your target version — Frappe/ERPNext v15 or v16, on Frappe Cloud or your own bench. We then build the app against that specification, install it on a staging site restored from your production data, and run a parallel pay cycle so you can compare our numbers against your current payroll employee by employee before anything is lodged for real. Typical delivery is 2-4 weeks from confirmed scope. You receive the full source in a git repository you own, installation and configuration on your environment, technical and user documentation, a live training session, and a post-go-live support window covering defects and your first live pay runs and lodgements.