October brings an important HMRC deadline for people who have recently developed new tax reporting responsibilities. If you need to complete a tax return for the previous tax year and have not previously submitted one, you may need to notify HMRC by 5th October 2026. September is therefore an excellent time to establish whether the requirement applies to you. Speaking with a professional tax advisor in Mychett can help you understand your circumstances and take action before the deadline.
What Is the 5th October Deadline?
HMRC requires certain taxpayers to tell them by 5th October if they need to complete a tax return for the previous tax year.
For 2026, the relevant tax year ran from 6th April 2025 to 5th April 2026. The requirement can apply if you need to complete a return and either have not submitted one before or previously registered but did not need to submit a return for 2024 to 2025.
Why Might You Need to Register?
A person’s financial circumstances can change significantly during a year.
For example, you may have:
- Started working for yourself
- Begun receiving rental income
- Developed additional sources of taxable income
- Disposed of assets that create reporting obligations
- Experienced another financial change requiring a tax return
Whether you need to register depends on your individual circumstances, so you should check rather than assume.
Why September Is the Time to Act
Waiting until October can leave little time to resolve uncertainty or gather the information you need.
Reviewing your position during September allows you to establish whether registration is necessary and start organising relevant records.
HMRC states that taxpayers who need to register should keep appropriate records, such as receipts and bank statements, so they can complete their return correctly.
What Happens After Registration?
Registering does not mean that your tax return or tax payment becomes due immediately.
For the 2025 to 2026 tax year, the standard online filing and payment deadline is 31st January 2027.
However, registering early provides time to prepare your records, understand your likely liability and avoid unnecessary last minute pressure.
Getting Professional Guidance
Tax reporting can become complicated when your circumstances change. Seeking professional advice early can help establish what HMRC expects and what information you need to provide.
Maratax offers clear, professional guidance tailored to individual circumstances.
If you are unsure whether you need to register before 5th October, contact Maratax and speak with an experienced tax advisor in Mychett before the deadline approaches.
