The new year always starts off strong in the world of accounting, with our first major deadline at the end of January, but the self assessment tax return deadline isn’t the only deadline you need to keep on top of this year.
Missing important dates can lead to penalties, interest charges, and unnecessary stress. To help you stay compliant and organised, here’s a handy guide to the most critical tax deadlines in 2025.
January 31, 2025 – Self-Assessment Tax Return Deadline
If you’re self-employed or required to file a self-assessment tax return, this is the big one. The deadline for submitting your online self-assessment tax return and paying any tax owed for the 2023/24 tax year falls on January 31. Ensure all your records are in order and submit your return well in advance to avoid last-minute complications.
See our guide to self-assessment tax returns for help!
April 5, 2025 – End of the 2024/25 Tax Year
The 2024/25 tax year officially ends on April 5, making this the last day to take advantage of any annual allowances and tax reliefs, such as your ISA allowance or pension contributions.
See some essential year end accounting tips for small businesses here.
April 6, 2025 – Start of the 2025/26 Tax Year
The new tax year begins on April 6. This is the ideal time to review your financial plans and update your PAYE coding notices or any other tax-related details.
May 31, 2025 – P60 Issuance Deadline
Employers must provide employees with their P60 forms by May 31. This document summarizes your total pay and tax deductions for the previous tax year.
July 6, 2025 – P11D Submission Deadline
Employers must submit P11D forms to HMRC and provide copies to employees by July 6. These forms detail benefits and expenses provided to employees during the tax year.
July 31, 2025 – Second Payment on Account
If you pay income tax through payments on account, the second installment for the 2024/25 tax year is due on July 31. Make sure you have funds set aside to meet this obligation.
October 5, 2025 – Register for Self-Assessment
If you’ve earned income that hasn’t been taxed at source during the 2024/25 tax year, October 5 is the deadline to notify HMRC and register for self-assessment.
October 31, 2025 – Paper Tax Return Deadline
For those who prefer to file a paper self-assessment tax return, the deadline is October 31. Filing online offers more flexibility, so consider switching if you’ve traditionally filed on paper.
December 30, 2025 – Online Self-Assessment for PAYE Tax Collection
If you owe less than £3,000 in tax and want HMRC to collect it via your PAYE tax code, submit your online self-assessment tax return by December 30.
By keeping these dates in mind and working proactively, you can avoid penalties and make the most of your tax planning. Need help staying on top of your tax obligations? Our team of accountants in Basildon can assist with ensuring your documentation is complete and compliant. Contact us today for expert advice and support.