UK Self Assessment Tax Deadlines: A Simple Guide

Tax season can be stressful with various deadlines to remember. Missing any could result in penalties, so here’s a simple guide to key UK tax deadlines:

Registering for Self Assessment: 5th October

If you’re filing a self-assessment tax return for the first time, register with HMRC by 5th October. This is required if you’re self-employed or have extra income like rental or savings interest.

Newly Self-Employed: Register online and get your Unique Taxpayer Reference (UTR).
Returning Self-Employed: Update your details with HMRC using a CWF1 form.
Additional Income: If you earn extra income but aren’t self-employed, fill out the form to register.

Registering on time ensures you’re ready to file your tax return.

Start of the New Tax Year: 6th April

The UK tax year begins on 6th April, often bringing new tax codes and allowance updates.

Personal Allowance: The amount you can earn before paying tax is £12,570 for 2024/25.
New Tax Codes: Check for any changes to avoid paying too much or too little tax.

Being aware of these changes helps prevent surprises later.

Payment on Account: 31st July

If you’re required to make payments on account, the deadline is 31st July. This is an advance payment toward next year’s tax bill based on what you owed last year.

Payment on Account: Spread out your tax payments to avoid a big bill in January.
Payment Methods: You can pay online, by BACS transfer, or by cheque.

Staying on top of this mid-year payment makes tax season easier.

Paper Filing Deadline: 31st October

If you’re filing a paper return, the deadline is 31st October. Though many prefer to file online, paper returns are still allowed.

Going Digital: HMRC is encouraging online filing, which is faster and easier.
Missed the Deadline? File online by 31st January instead.

Final Deadline for Online Submissions: 31st January

31st January is the final day to file your online self-assessment and pay any due taxes. Missing this deadline could lead to penalties.

Payment on Account: You may also need to make your first payment on account for the next year.
Why File Early? Early submission gives you time to fix any issues and ensures you’re set for the next year.

For more information, visit the official HMRC website.

How DataTracks Can Help

Need assistance with iXBRL compliance for HMRC CT600 filings? Our experts can help ensure you’re always in compliance. Contact us at +44 (0) 203 608 8035 or email enquiry@datatracks.co.uk.