Underpaid $300/week for 1 year — How Much Back Pay?
Calculate how much you are owed in back pay if you have been underpaid by $300 per week for 1 year.
Last verified: 1 July 2025You are owed approximately $15,990.00 in back pay
Based on $300 per week underpayment over 1 year, plus estimated interest at 5% p.a.
Total Back Pay Calculation
| Underpayment rate | $300 per week |
| Weekly underpayment | $300.00 |
| Duration | 1 year (~52 weeks) |
| Unpaid wages | $15,600.00 |
| Estimated interest (~5% p.a. simple) | $390.00 |
| Total owed (estimate) | $15,990.00 |
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.
Time Limits — 6-Year Limitation Period
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 1 year is within the 6-year limit. However, the sooner you act, the more you can recover — and the underpayment may still be ongoing.
How to Claim Your Back Pay — Step by Step
- Gather your evidence: Collect payslips, timesheets, rosters, bank statements, and your employment contract. The more documentation you have, the stronger your claim. Screenshot any relevant messages or emails.
- Check your award or agreement: Use our Award Finder to identify the correct Modern Award and minimum rates for your job classification and level.
- Raise it with your employer in writing: Send a formal letter or email outlining the underpayment, the period, and the total amount owed. Many employers will rectify underpayments voluntarily once notified. See our template letter below.
- Contact the Fair Work Ombudsman: If your employer refuses to pay or does not respond within 14 days, lodge a complaint at fairwork.gov.au or call 13 13 94 for free advice.
- Small Claims Court: For claims under $20,000, apply to the Small Claims division of the Federal Circuit and Family Court. You do not need a lawyer. For larger claims, you may need legal representation — many employment lawyers offer a free initial consultation.
Template Letter — Requesting Back Pay
[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 $300 per week for the period of 1 year, resulting in a total underpayment of approximately $15,600.00.
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.
Compare Back Pay Amounts (Weekly Underpayment)
See how total back pay varies by underpayment amount and duration (wages only, excluding interest):
| Underpaid | 3 months | 6 months | 1 year | 18 months | 2 years | 3 years |
|---|---|---|---|---|---|---|
| $50/wk | $650.00 | $1,300.00 | $2,600.00 | $3,900.00 | $5,200.00 | $7,800.00 |
| $100/wk | $1,300.00 | $2,600.00 | $5,200.00 | $7,800.00 | $10,400.00 | $15,600.00 |
| $150/wk | $1,950.00 | $3,900.00 | $7,800.00 | $11,700.00 | $15,600.00 | $23,400.00 |
| $200/wk | $2,600.00 | $5,200.00 | $10,400.00 | $15,600.00 | $20,800.00 | $31,200.00 |
| $300/wk | $3,900.00 | $7,800.00 | $15,600.00 | $23,400.00 | $31,200.00 | $46,800.00 |
| $500/wk | $6,500.00 | $13,000.00 | $26,000.00 | $39,000.00 | $52,000.00 | $78,000.00 |
Know Your Hourly Underpayment Instead?
Need a More Detailed Calculation?
Our interactive calculator includes superannuation shortfall, penalty rates, and custom hours. Check if you are being underpaid or find your correct award rate.
Frequently Asked Questions
How much back pay am I owed if underpaid $300/week for 1 year?
If you were underpaid by $300 per week for 1 year ($300.00/week underpaid), you are owed approximately $15,600.00 in unpaid wages plus an estimated $390.00 in interest, totalling approximately $15,990.00.
How do I claim back pay from my employer?
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.
How far back can I claim underpaid wages in Australia?
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.
Can I claim interest on underpaid wages?
Yes. Courts can award interest on underpaid wages, typically at around 5% per annum simple interest. In this scenario, estimated interest over 1 year is approximately $390.00. The actual rate may vary depending on the court and circumstances.
What evidence do I need to claim back pay?
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.
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.