Calculate how much you are owed in back pay if you have been underpaid by $7 per hour for 18 months.
Last verified: 21 May 2026If you've been underpaid, your employer must back-pay the difference plus 12% super on the shortfall. There's no time limit on claiming wages owed, but the Fair Work Ombudsman recommends acting within the 6-year limitation period to preserve your claim.
AIGot a tricky case? Ask FairWork Mate AI — 1 free question, no signup →You are owed approximately $21,526.05 in back pay
Based on $7 per hour underpayment over 18 months (38 hours/week = $266.00/week underpaid), plus estimated interest at 5% p.a.
| Underpayment rate | $7 per hour |
| Hours per week (full-time) | 38 |
| Weekly underpayment | $266.00 |
| Duration | 18 months (~78 weeks) |
| Unpaid wages | $20,748.00 |
| Estimated interest (~5% p.a. simple) | $778.05 |
| Total owed (estimate) | $21,526.05 |
This estimate does not include unpaid superannuation, penalty rates, or overtime. Actual amounts may be higher. Use our Back Pay Calculator for a more detailed calculation.
Important: Under the Fair Work Act, you can claim back pay for up to 6 years from the date you lodge your claim. Any underpayment older than 6 years is statute-barred and cannot be recovered.
Your underpayment period of 18 months is within the 6-year limit. However, the sooner you act, the more you can recover — and the underpayment may still be ongoing.
[Your Name]
[Your Address]
[Date]
[Employer Name]
[Employer Address]
Re: Underpayment of Wages
Dear [Manager/HR],
I am writing to formally notify you that I believe I have been underpaid in my role as [Job Title] at [Company Name].
Based on my calculations, I have been underpaid by approximately $7 per hour for the period of 18 months, resulting in a total underpayment of approximately $20,748.00.
Under the Fair Work Act 2009, I am entitled to recover these unpaid wages. I request that this amount be paid within 14 days of receipt of this letter.
If I do not receive a satisfactory response, I intend to lodge a formal complaint with the Fair Work Ombudsman.
I am happy to discuss this matter and provide any supporting documentation.
Yours sincerely,
[Your Name]
This is a general template only and does not constitute legal advice. Modify it to reflect your specific circumstances.
See how total back pay varies by underpayment amount and duration (wages only, excluding interest):
Our interactive calculator includes superannuation shortfall, penalty rates, and custom hours. Check if you are being underpaid or find your correct award rate.
If you were underpaid by $7 per hour for 18 months (working 38 hours/week, that's $266.00/week underpaid), you are owed approximately $20,748.00 in unpaid wages plus an estimated $778.05 in interest, totalling approximately $21,526.05.
Start by raising the issue directly with your employer in writing, detailing the amounts and dates of underpayment. If they refuse to pay, contact the Fair Work Ombudsman on 13 13 94 or lodge a complaint at fairwork.gov.au. For claims under $20,000, you can use the Small Claims division of the Federal Circuit Court without a lawyer.
Under the Fair Work Act 2009, you can claim back pay for up to 6 years from the date you file your claim. This is a strict limitation period. Any underpayment older than 6 years is statute-barred and cannot be recovered. Act quickly to preserve the maximum claim amount.
Yes. Courts can award interest on underpaid wages, typically at around 5% per annum simple interest. In this scenario, estimated interest over 18 months is approximately $778.05. The actual rate may vary depending on the court and circumstances.
You should gather payslips, timesheets, rosters, bank statements showing payments received, your employment contract or letter of offer, and any applicable Modern Award or Enterprise Agreement. Screenshots of text messages or emails discussing your pay rate are also useful evidence.
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FairWork Mate is an independent commercial service. We are not affiliated with, endorsed by, or associated with the Fair Work Ombudsman, the Fair Work Commission, or any Australian Government agency. Content is general information and estimates only — not legal, financial, or tax advice. Always verify with the Fair Work Ombudsman (13 13 94) or a qualified professional.
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