New Year, Same HMRC Deadline: What You Need To Know About Self Assessment
A new year often brings a sense of reset. Fresh plans, big goals, and the feeling of a clean slate.
Unfortunately, HMRC does not operate on new year energy.
No matter how motivated you feel in January, your Self Assessment tax return still needs to be filed and paid by 31 January. Miss it, and the consequences can follow you straight into the year ahead.
The Self Assessment Deadline Does Not Move
Every year, the deadline remains the same.
If you are required to file a Self Assessment tax return, it must be:
Filed by 31 January
Paid by 31 January
This applies whether you are self employed, a company director taking dividends, or earning income outside PAYE.
HMRC does not make allowances for busy periods, holidays, or good intentions.
What Happens If You Miss the Deadline
Missing the Self Assessment deadline triggers automatic penalties. These are not warnings. They apply immediately.
You could face:
A £100 late filing penalty
Daily penalties if the return remains outstanding
Interest on any unpaid tax
Additional charges the longer it is left
Even if you owe no tax, the penalties for late filing still apply. This often catches people out.
Why January Becomes So Stressful
For many people, January panic is not caused by the tax itself. It is caused by leaving things too late.
Scrambling for paperwork, guessing figures, or rushing a return increases the risk of mistakes. Mistakes can lead to incorrect tax bills, missed claims, or HMRC follow up questions later on.
This stress is avoidable with better planning and support.
If You Have Not Filed Yet, Act Now
If your return is still outstanding, the best thing you can do is act immediately.
File your return as soon as possible, even if you are unsure about payment. Filing late causes penalties. Paying late causes interest. These are separate.
If you are struggling to pay, HMRC may offer Time to Pay arrangements, but only once your return is filed.
How To Avoid This Panic Next Year
If this feels like a familiar pattern, it is a sign that something needs to change.
Better support throughout the year can help you:
Keep records organised
Understand your tax position earlier
Plan payments in advance
Avoid last minute stress
Reduce the risk of penalties
Speaking to your accountant once a year is often not enough. Regular check ins and forward planning make a huge difference.
The Bottom Line
A new year should feel like a fresh start, not a financial headache.
HMRC deadlines do not change, but how you prepare for them can. Filing on time, planning ahead, and having the right support in place will help you start the year with clarity instead of stress.
If you want help filing your Self Assessment or putting better systems in place so this does not happen again, get in touch. We are here to help.
Meet Lewis
Lewis is a professional accountant and founder of Rhombus Accounting. He regularly shares his knowledge and best advice here on his blog and on other channels such as LinkedIn.
Book a call today to learn more about what Lewis and Rhombus Accounting can do for you.
