Everything You Need to Know About Self Assessment Tax Deadlines and Penalties

Self Assessment is a means by which HMRC collects Income Tax from individuals whose income is not entirely covered through PAYE. If you are self-employed, are a landlord, or you have other income, you probably need to submit a Self Assessment tax return annually.

Missing deadlines or mistakes will incur penalties. Being aware of important dates and filing in the right way helps to save stress and unnecessary expense. Fortunately, clever software such as Nomi can make it easier.

Let's take a look at the main deadlines, penalties, and how to get ahead in easy, clear steps.

Who Must Submit a Self Assessment Return?

• Self-employed individuals, such as sole traders
• Business partnership partners
• Company directors (if they receive income not taxed under PAYE)
• Individuals with income from letting property
• Individuals receiving tips or commissions
• Individuals with savings, investments, or dividend income
• Individuals claiming certain tax reliefs related to income
• Individuals with foreign income that they must pay tax on

Key Self Assessment Deadlines

• 5 October – Deadline to register for Self Assessment if you are self-employed or must file for another reason
• 31 October – Paper tax returns must arrive at HMRC
• 31 January – Online tax return due date for last tax year
• 31 January – Pay any tax due for last tax year
• 31 July – Pay your second payment on account if necessary

Key Payment Dates

• 31 January – First payment on account (if you need to make one)
• 31 July – Second payment on account (if you need to make one)
• Balancing Payment – Payable if you have any further tax to pay after payments on account

 Penalties for Late Filing

• £100 penalty – If your return is between 3 months late
• £10 a day penalties – After 3 months, up to a 90-day maximum of £900
• £300 or 5% of the tax due (whichever is greater) – After 6 months late
• Another £300 or 5% of the tax owed – If still late after 12 months
• Additional penalties – For severe situations such as concealing income

Late Payment Penalties

• 5% of unpaid tax – If payment is late by 30 days
• Additional 5% – If payment is late by 6 months
• Additional 5% – If payment is late by 12 months
  

Reasons Why People Miss Deadlines

• Forgetting to enroll for Self Assessment in time
• Misinterpreting who needs to file
• Leaving papers until the very end
• Unaware of total amount due
• Technical issues when filing online

Avoiding Penalties

• Register in good time if you are likely to have to file
• Maintain precise records throughout the year
• Save reminders for relevant dates
• Apply sound book-keeping or use accounting software
• Begin completing your tax return sufficiently early before deadline
• Seek the advice of an expert if anything is unclear to you

Information You'll Need for Your Return

• Your Unique Taxpayer Reference (UTR) number
• Your National Insurance number
• Details of all your earnings
• Details of any you wish to claim for expenses or tax relief
• P60 or P45 certificates if you were working
• Bank and building society accounts
• Details of any savings or investments income
• Details of pension payments or gifts to charity

What if You Get Something Wrong?

• If you see an error, you can put it right within 12 months of the original deadline
• Minor errors can usually be corrected without penalties if you are truthful
• If HMRC detects an error that you attempted to conceal, fines can be substantially higher
• Double-check your amounts and details before filing

How Using Software Such as Nomi Can Assist?

• Automatically track income and expenses
• Easily upload receipts and documents
• Compute tax due with fewer inaccuracies
• Remind you of near-future deadlines
• Submit returns to HMRC directly
• Save time and prevent last-minute anxiety

Advantages of Filing in Advance

• More time to rectify errors if necessary
• Discover how much tax you need to pay well in advance of the deadline
• Better plan your finances
• Less risk of penalties
• Sense of security knowing it is complete and filed accurately

Tips for Seamless Filing

• Do a little at a time monthly rather than waiting until the last minute
• Save copies of key documents digitally
• Know what you can claim as expenses
• Utilize accounting software to simplify bookkeeping
• Stay up-to-date with tax regulations that can impact you
• Seek advice from an accountant if you are uncertain

Why Choose Nomi

• Nomi has been built to suit the needs of UK accountants, small businesses, and individuals. Nomi provides:
• Straightforward online filing directly to HMRC
• Quick tracking of income and expenses
• Intelligent reminders on deadlines
• Cloud storage of your documents securely
• Excellent support staff to assist you when needed
• Updates regularly to keep you in compliance

Conclusion

Completing a Self Assessment tax return need not be stressful. It is all about knowing the deadlines, having decent records, and employing clever cloud accounting software such as Nomi. It will keep you on track and prevent expensive fines. Whether a freelancer, landlord, or sole trader, it makes tax season so much less painful.
Nomi assists UK companies and individuals with filing tax returns with confidence. No stress, no late filings, just smart and easy tax management.