When Is My Tax Return Due If I Use a Tax Agent?

How the tax agent lodgment program works

If you lodge your own return, the 2025-26 deadline was 31 October 2026. Because 31 October fell on a Saturday this year, the ATO gave self-preparers until 11:59 pm local time on Monday 2 November 2026.

Registered tax agents have a lodgment program with the ATO that gives their clients later due dates. To be covered for 2025-26 returns, the agent had to add you to their client list by 31 October 2026. The ATO told agents that the weekend did not move this cut-off, so 31 October itself was the last day.

Your exact due date depends on your situation, and your agent can see it for each client. Some new clients also have to nominate their agent through client-to-agent linking before the agent can add them.

Which due date applies to you?

The ATO sets individual due dates under the 2026-27 lodgment program like this. Your agent can see the actual date for each client, so check with them rather than assuming 15 May.

Prosecuted clients may have a different date set out in their ATO letter. Large and medium trusts have other dates, but those do not affect individuals.

• 31 October 2026: one or more prior-year returns were outstanding at 30 June 2026
• 31 March 2027: your latest return resulted in a tax liability of $20,000 or more
• 15 May 2027: all other individuals, including new registrations
• 5 June 2027: a concession for 15 May returns, if any payment is also made by 5 June

When do you have to pay?

For returns due on 15 May, the payment date depends on when the return is lodged. Lodging early does not always mean paying early.

Worked example: your agent lodges your 2025-26 return on 1 March 2027 and it shows tax to pay. 1 March falls in the 13 February to 12 March 2027 window, so payment is due by 21 April 2027.

For returns not due on 15 May, payment is due on the later of 21 days after the lodgment due date or 7 business days after your notice of assessment issues. Returns lodged late, or default assessments, have payment due 21 days after the lodgment due date.

• Lodged up to 12 February 2027: pay by 21 March 2027
• Lodged 13 February to 12 March 2027: pay by 21 April 2027
• Lodged from 13 March 2027: pay by 5 June 2027

What if you missed the 31 October cut-off?

If you were not on an agent's client list by 31 October 2026, you will not get a lodgment program due date for your 2025-26 return. If you previously lodged yourself, the ATO says you are not covered by the agent's program and may need to lodge by an earlier due date. For self-preparers that date was 2 November 2026.

The fix is to lodge as soon as you can. The ATO generally does not issue a failure to lodge penalty for a late return that results in a refund or nil, and it usually warns you before applying one. If you owe tax, late lodgment can bring a penalty and interest, so contact your agent or the ATO early.

Safe harbour and checking your agent is registered

If you use a registered tax agent, safe harbour can protect you from a failure to lodge penalty. It applies if you gave your agent all the relevant information in time and the agent's failure was not reckless or intentional. Keep evidence of what you sent and when.

Tax agents must be registered with the Tax Practitioners Board, and you can check anyone on the TPB public register. The ATO says it has stopped more than 10,000 returns this tax time that it suspects were prepared by unregistered preparers.

When to get help

If you are not sure whether you were added in time, or you have older returns still outstanding, ask your agent to check your due date in their client list now. It takes a few minutes and avoids guessing.

Acquire Strategic Accounting is a registered tax agent in Brisbane, with offices in Victoria Point and Jimboomba. We can confirm your due date and lodge any overdue returns.