PAYG vs Estimated Tax: Why They Don't Match

Overview: PAYG withholding is a best-effort estimate of what you’ll owe at the end of the year. The tables assume one employer, no offsets, no HELP debt, and steady earnings. Real life rarely matches that. Here’s what drives the difference.

Why PAYG can be short (or over)

• Multiple jobs: Each employer taxes you as if they’re your only job. Combined income pushes you into a higher marginal rate.
• HELP / MLS: ATO adds compulsory HELP repayments and the Medicare Levy Surcharge when you lodge. Employers only add them if you’ve told them to.
• Lumps and bonuses: PAYG tables spread tax evenly across the year. A one-off bonus might need more tax withheld than the table suggests.

How to forecast the shortfall

1. Add up year-to-date gross income across all jobs.
2. Run the figure through the Income Tax Calculator with HELP toggled on if you have a debt.
3. Subtract total PAYG withheld (from payslips). The difference is what you still owe (or could be refunded).

Fixing it before EOFY

• Adjust withholding: Ask payroll to withhold an extra dollar amount each pay or tick the HELP/MLS boxes on your TFN declaration.
• Make voluntary payments: You can send an extra amount via BPAY to the ATO. It shows as a credit on your myGov account.
• Plan for the bill: If the shortfall is unavoidable, park the cash in a high-interest account until lodgement and pay on time to avoid interest.

Next payroll step

If you are reconciling withheld tax against real payroll records, move from the estimate into the underlying documents:

• Use the PAYG withholding calculator to check the per-pay estimate
• Build cleaner payroll records in the payroll document hub
• Generate a compliant payslip if you need to recreate or standardise payroll output

PAYG is a guide, not a promise. By running the numbers mid-year and making adjustments, you avoid the shock of a tax bill when the assessment arrives.