ADP has operated in Australia for decades and offers both cloud payroll software and outsourced managed payroll, so AU payroll is well established. It also supports New Zealand payroll as part of its ANZ operations.
The consideration for complex enterprises is depth of award and EBA interpretation. ADP's product investment is spread across a global HCM suite and 140+ countries; if your organisation runs many modern awards or EBAs with layered shift penalties and allowance stacking, it's worth testing ADP against your actual scenarios before committing.
For multinationals, ADP's GlobalView (enterprise, multi-country) and Celergo (aggregation across 140+ countries) sit alongside its local AU cloud software and managed payroll for consolidating payroll across many jurisdictions.