As the online filing deadline approaches, it’s essential to gather all the documents and information HMRC requires for an accurate tax return. In the 2023 – 2024 tax year, around 1.1 million people reportedly missed the 31 January 2025 deadline, and were issued an immediate £100 late filing penalty.
If you’re wondering, “what do I need to complete a tax return?” before the 31 January 2026 deadline, we’ve put together a clear, comprehensive checklist of everything to prepare before submitting your return.
What Do I Need for my Tax Return?
If you’re required to complete a tax return, there are several key documents you’ll need to gather before you begin. This includes your personal information, financial records, and details of all income received throughout the tax year. Organising everything in advance helps ensure your return is accurate, submitted on time, and that you claim any allowances or reliefs you’re entitled to.
A quick overview of what you’ll need includes:
- Key personal details
- Essential income documents
- Records of expenses and deductions
- Any supplementary forms required for your income type
- Awareness of submission deadlines (online vs paper)
What Personal Information Do I Need to Complete My Tax Return
When it comes to your personal information, you’ll primarily need your Unique Taxpayer Reference (UTR) and your National Insurance (NI) Number to complete a tax return in the UK. Your UTR is a 10-digit code that can be found on your HMRC Personal Tax Account, or on any official correspondence letters from HMRC regarding previous tax returns.
You will also need your Government Gateway User ID, and basic personal details such as your address, date of birth, and contact details.
To summarise:
- Unique Taxpayer Reference (UTR)
- National Insurance Number
- Government Gateway User ID
- Basic personal details: name, address, date of birth, contact details
Income Documents to Gather Before You File
You should also gather documentation covering all forms of income you have received throughout the year. This includes employment records such as your P60, P45, and any P11D forms, as well as income and expense records if you are self-employed.
You can find the specifics of what income documents you need here:
- Employment income: P60, P45, P11D
- Self-employment income: income and expense records
- Rental income: statements and allowable expense records
- Savings and investment income: bank interest certificates, dividend statements
- Pension income: state or private pension details
- Any other taxable income: e.g., foreign income, student loan repayments
- Tax already paid: PAYE information or payment on account details
When Is the Tax Return Submission Deadline?
Understanding your tax return deadlines is essential to maintaining compliance and avoiding unnecessary penalties. In the UK, paper tax returns must be submitted by 31 October, while online submissions are due by 31 January. Missing these dates can result in immediate fines and interest charges, which makes timely preparation crucial.
If you need clarity on which deadline applies to you or support in preparing your documentation, ST Accountancy provides expert tax services in Ipswich to ensure your return is completed accurately and submitted on time.
Conclusion
Completing a tax return is far easier when you have the right information, organised records, and access to specialist advice. By preparing in advance and understanding your obligations, you can file confidently, reduce the risk of errors, and maximise any reliefs or allowances you’re entitled to.
For reliable support and a streamlined filing process, ST Accountancy is a tax advisor in Ipswich that delivers trusted, professional expertise across all areas of personal and business taxation.
Contact our team today to ensure your tax affairs are handled accurately and efficiently, helping you stay compliant while strengthening your overall financial position.