Every job in a financial year goes on one tax return, including the week you did in a kitchen and never went back to. Each employer reports separately to the ATO, so the return has to reconcile against the combined total.
How does the ATO already know where you worked?
Through Single Touch Payroll, which requires every Australian employer to report wages, tax withheld and super to the ATO at each pay run rather than once a year. By the time you come to lodge, the ATO holds the complete list.
Two consequences follow. Forgetting an employer does not leave income off a return; it lodges a return that does not match the record. And a job you have no payslips for is not lost income, because the reporting came from the employer and not from you. A festival shift paid through a temp agency six months ago is in there whether or not you remember the agency's name.
What goes wrong when an employer is left off?
The return is processed at the figure you reported, the refund is paid, and the correction arrives afterwards. The ATO spots the gap against its own record and issues an amended assessment adding the missing income, commonly weeks or months later.
By then the refund is generally spent. The amended assessment creates a debt, the General Interest Charge runs on it from the original due date, and a substantial omission can attract a penalty on top. Lodging once against the full record avoids all of it.
Where is the refund actually concentrated?
At one employer, almost always, rather than spread evenly across them. The useful exercise is comparing rather than adding: divide tax withheld by gross wages for each employer separately and see which one sits meaningfully above 15%.
Two patterns produce that. An employer not registered with the ATO as a working holiday maker employer must withhold at foreign resident rates rather than 15%, common on farms and with small regional businesses, and the excess is recoverable. A first job where your TFN arrived late shows weeks at 45%, a difference of 30 cents in every dollar for that period. Identifying which employer it was tells you where your year's money went.
- One employer well above 15%: an unregistered employer or a late TFN, and a substantial refund
- All employers at 15%: the refund comes from the Medicare levy exemption and deductions instead
- Combined income above $45,000: the rate steps to 30% and the withholding may have been short
Can multiple jobs leave you owing money?
Yes, and it catches people who assume more jobs means a bigger refund. Each employer withholds against the income they pay you without knowing about the others, as though its job were your only one.
Working holiday makers have no tax free threshold, so the usual Australian version of this problem does not arise, but the bracket effect does. Combined income above $45,000 moves into the 30% bracket while each individual employer may still have been withholding at 15%, and the shortfall appears at the end of the year as an amount owing. Three concurrent casual jobs through a busy summer is the usual shape.
What is worth keeping when you work several jobs?
Anything not already in the ATO record, which is a shorter list than most people expect. The income side comes through Single Touch Payroll, so payslips are a cross check rather than the source, useful for proving what should have been reported if an employer never finalised.
- Payslips or final summaries, as a check against the ATO figures
- Details of any cash payments never reported through payroll, which still have to be declared
- Work related expenses, recorded against the job they belong to
- Travel between two workplaces on the same day, which can be deductible where travel from home is not
When can a multi employer return be lodged?
Once every employer has finalised, and not before. Income statements show as not tax ready until the employer completes its end of year reporting, and one employer finalising late is enough to make the whole return premature.
This is where multi employer years get amended unnecessarily. Lodge in early July against three finalised employers and one that has not finished, and the fourth arrives afterwards and the assessment changes. Waiting for all of them costs a fortnight; amending afterwards costs considerably more.