If you lodge your own tax return, it's due on 31 October. This year that's a Saturday, so the due date moves to the next business day: Monday 2 November 2026.
Most returns go online now, but tax time still brings paper: an amendment, an objection, a non-lodgment advice, or a reply to an ATO letter with the documents it asked for. Here's where each goes and how to get it there on time. The addresses are from the ATO's website, checked on 21 October 2026.
It counts when it arrives, not when it's posted
The ATO treats a posted document as lodged on the day it's delivered, so a postmark doesn't save a late one. Allow for the delivery time as well as the posting.
- Pay by 2:30pm Melbourne time on a business day and we post it that day.
- Express Post usually arrives the next business day within Australia Post's network. Regular post takes 3 to 7 business days.
- For Monday 2 November: by regular post, send it by Thursday 22 October. By Express Post, Thursday 29 October leaves a day spare, and Friday 30 October is the last day.
The tax return itself
A paper tax return goes on the ATO's own form, Tax return for individuals (NAT 2541), which you order from its Publications Ordering Service rather than download. We print onto plain paper, so we can't post a return for you. Lodge it with myTax, where most refunds come within 10 business days, or post the ATO's form to GPO Box 9845 in your capital city, where paper returns take up to 50 business days.
Where everything else goes
| What you're sending | Address |
|---|---|
| A request to amend your return | Australian Taxation Office, PO Box 3004, PENRITH NSW 2750 |
| An objection to an ATO decision | Australian Taxation Office, PO Box 3524, ALBURY NSW 2640 |
| A non-lodgment advice | Australian Taxation Office, GPO Box 9845, your capital city and its postcode, such as SYDNEY NSW 2001 |
| A reply to an ATO letter, such as a review or audit | The address on the ATO's letter |
| Any other letter | Australian Taxation Office, GPO Box 9990, your capital city and its postcode, such as SYDNEY NSW 2001 |
Amending your return
Spotted a mistake after lodging? If you lodged online, amend it in myTax. Otherwise, use the ATO's Request for amendment of income tax return for individuals, or write a letter. A letter needs your TFN, full name, postal address, phone number and bank details, the year, the question number, the amounts and correct totals, and why. It ends with the declaration the ATO gives, signed and dated. Either way, it can take up to 50 business days.
Objecting to a decision
If you disagree with an assessment or another ATO decision, you can object on the ATO's Objection form for taxpayers or by letter. Say why you think the decision is wrong, then sign and date it. Most individuals have 2 years from their notice of assessment to object, and some have 4.
Not lodging a return this year
If you don't need to lodge, tell the ATO with a non-lodgment advice by the same date as the return. You can download the form, fill it in and post it.
Replying with documents
If the ATO asks for documents for a review or an audit, send copies, not originals: it can't return them. Make sure they're clear and readable, and don't send a USB drive. Post them to the address on the ATO's letter.
Upload up to 10 files at once, such as your reply, the ATO's letter and photos of receipts, and we post them together in one envelope, up to 80 pages.
Sign it before you upload it
We print exactly what you upload, so sign the letter or form first. On an iPhone or iPad, open the PDF in Files and use the Markup pen. On Android or a computer, Adobe Acrobat Reader's Fill & Sign does the same. If a form says it must be signed in ink, ask the ATO whether a printed copy will do.
Close to a deadline? Fax it
The ATO also takes amendments by fax on 1300 730 239 and objections on 1300 139 031, and a fax arrives in minutes. unofax, our sister service, faxes a PDF for $0.59 a page, with delivery confirmation by email.
What it costs
$10 by regular post, folded, for up to 12 pages, or $20 by Express Post for up to 20 pages, then $0.30 a page, GST included. Signature on delivery is $6 extra.
Every letter is tracked, and we email you the tracking number once it's posted, so you can show when it arrived. Keep a copy of what you send, and your tax records for 5 years from the day you lodge.
Questions
When is the 2026 tax return due?
If you lodge it yourself, by 31 October. In 2026 that's a Saturday, so the due date is the next business day, Monday 2 November. If you use a registered tax agent, they may have a later date for you.
Is a posted document lodged on the day I post it?
No. The ATO treats a posted document as lodged when it arrives, so allow for delivery. Express Post usually arrives the next business day, and regular post takes 3 to 7 business days.
Where do I post an amendment to my tax return?
To Australian Taxation Office, PO Box 3004, PENRITH NSW 2750. You can also fax it to 1300 730 239, or amend it in myTax if you lodged online.
What is the penalty for lodging a tax return late?
For an individual, $364 for every 28 days or part of it that the return is late, up to $1,820. The ATO says it generally doesn't apply it for an isolated late return, or when the return gives a refund or a nil result.
Can Unopost post my paper tax return?
No. A paper return has to be on the ATO's own form, which it posts to you. We can post amendments, objections, non-lodgment advice, replies to ATO letters and other letters to the ATO.
The short version
Lodge your return with myTax or on the ATO's paper form by Monday 2 November. For everything else, sign it, upload it, and send it by Express Post if the date is close, since it counts when it arrives. The ATO's other addresses are on our page for posting documents to the ATO.
More on this: Post documents to the ATO