The Core Filing Mechanics
Filing US taxes from Australia layers on top of, not instead of, your Australian obligations to the ATO. The two systems run on different tax years (Australia's runs July 1 to June 30, the US uses the calendar year), which means you'll often be estimating one year's figures before the matching Australian return is finalized.
Form 1040 and the Automatic Extension
The standard deadline is April 15, but Americans living abroad get an automatic extension to June 15. Any tax owed still accrues interest from April 15, so estimate and pay by then if you expect a balance due. A further extension to October 15 is available on request (Form 4868).
Form 1116: Foreign Tax Credit
Because Australian tax rates usually exceed US rates, Form 1116 is the workhorse form for most Americans here. It converts Australian income tax paid into a dollar-for-dollar credit against your US liability, and unused credits carry forward up to ten years, which matters if you had a high-earning year in Australia followed by a lower-income year.
Worked Example: Sydney Salary
An American software engineer in Sydney earns AUD 160,000 (about $105,000 USD). Australian tax plus Medicare Levy on that income runs roughly AUD 44,000 (about $29,000 USD), an effective rate above 27%. Converted into a Foreign Tax Credit, that fully offsets the US tax otherwise due on the same salary, leaving little to no US liability, before superannuation reporting is even considered.
FBAR: FinCEN Form 114
Required if the combined balance of all foreign financial accounts, checking, savings, and superannuation, exceeds $10,000 USD at any point in the calendar year. Given that superannuation alone often exceeds this on its own, nearly every American working in Australia has an FBAR obligation from year one. Filed electronically, due April 15 with an automatic extension to October 15.
FATCA: Form 8938
A separate, higher threshold that attaches to your Form 1040 itself: generally $200,000 in specified foreign assets at year-end (or $300,000 at any point) for a single filer abroad, doubled for married filing jointly. Superannuation balances and any Australian brokerage or property investment count toward this threshold.
Streamlined Compliance for Late Filers
If you've lived in Australia for years without realizing you needed to file US returns, a common situation given how normal citizenship-based taxation feels invisible until it isn't, the IRS Streamlined Foreign Offshore Procedures let you catch up on the last three years of returns and six years of FBARs without the standard failure-to-file penalties, provided the omission was non-willful.