Sunita Somvanshi
ATO Tax Deduction Warning Letters Explained: 5 Red Flags, Penalties & How to Respond via myGov
Australians opening their myGov inbox are finding an ATO tax time warning letter about their work-related deductions. The ATO has sent follow-up letters to people whose claims looked out of line. Here is what triggered the flag and what to do next.
The ATO flags five common claim patterns.
1. Claims that sit well outside the benchmark for your occupation.
2. Internet, phone and electricity claims that treat 100% of the bill as work use when you work from home.
3. Car expenses for driving between home and work.
4. Everyday clothing, such as plain business wear, claimed as a work expense.
5. Rental property repairs and interest claimed incorrectly.
Not every letter means the same thing. The table below shows the three main contact types (source: Zawat Tax Guide).
| Contact type | What it is | What you do |
|---|---|---|
| Prompter letter | A nudge to review claims the ATO considers unusual. It is not an audit. | Check your claims and amend if needed. |
| Data-matching notice | The ATO compares your return with information it holds from other sources. | Correct any mismatch. |
| Formal audit | A detailed examination of your records. | Provide the records requested. |
Wrong claims carry costs. If your total work-related expenses are above $300, you need written evidence. Keep records for all claims. Shortfall penalties range from 25% to 75% of the extra tax owed. On top of that, the General Interest Charge (currently 7.51% per annum for the fourth quarter of 2026) applies (source: Nanak Accountants).
ATO tax time warning letter: 5-step response checklist and how to spot myGov phishing scams
Follow these steps if a letter arrives.
1. Read the letter and note which deduction it names.
2. Gather your receipts, logs and bank records for that claim.
3. Remove anything you cannot prove or that does not meet the rules.
4. Amend your return in myGov. You have two years from the date of your notice of assessment to do so.
5. Keep your records and a copy of the amendment.
Scammers copy ATO letters, so check before you act. Call the ATO on 1800 008 540 to confirm a letter or message is real. The ATO does not send unsolicited emails or SMS with clickable links or QR codes. Do not tap one, even if it looks official. Log in to myGov yourself instead.
The ATO updated its Standard Deduction guidance on 2 November 2026, and that affects how work-related claims are treated from the 2026-27 income year (source: ATO Standard Deduction Guide). For more, read ATO tax payment changes, CBA banking and mortgage coverage, and RBA rate and mortgage impact guides.
Two groups of taxpayers are drawing extra attention. Early lodgers who filed before pre-fill data was finalised were more than twice as likely to trigger an adjustment. Late lodgers who filed after 31 October are also being flagged.
What is an ATO prompter letter?
It is a letter asking you to review specific deductions in a return you have already lodged. It is not an audit.
How long do I have to amend my return?
You have two years from your notice of assessment.
Do I need receipts for every claim?
If your total work-related expenses are above $300, you need written evidence. Keep records for all claims.
How do I know the letter is real?
Call 1800 008 540. The ATO does not send unsolicited emails or SMS with clickable links or QR codes.
Before you act, run through this list. Check the five triggers. Verify the letter by phone. Gather your records. Amend through myGov within two years. Pay any shortfall quickly, because the General Interest Charge keeps running.
