Taxpayers who miss the January 31, 2026 deadline for Self Assessment will face automatic £100 fines from HM Revenue and Customs. Late filing can lead to additional penalties and interest, making timely submission essential for millions of households across the UK.
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HMRC to Issue £100 Fines
The initial £100 penalty applies automatically to taxpayers who fail to submit their tax return or make the first payment by 11:59 pm on January 31, 2026. Over 12 million people, including the self-employed, landlords, and those with extra income, are required to complete Self Assessment each year. Timely filing avoids both penalties and interest charges, which begin accruing immediately after the deadline passes.
| Date | Requirement | Consequence if Missed |
|---|---|---|
| 31 January 2026 | File tax return and make first payment | £100 penalty plus interest |
| 31 July 2026 | Second instalment if applicable | Further penalties and interest |
Escalating Penalty Structure
HMRC penalties increase the longer a tax return remains unpaid or unfiled. Three months after the deadline, daily fines of £10 apply up to £900. After six months, a further penalty of 5 percent of tax owed or £300 is added. Twelve months late triggers an additional 5 percent of tax owed or £300.
- Initial £100 penalty immediately after the deadline
- £10 daily fines after three months, up to £900
- 5 percent of tax owed or £300 after six months, whichever is higher
- Another 5 percent of tax owed or £300 after twelve months, whichever is higher
A taxpayer who delays filing could face total penalties exceeding £1,600, excluding the amount of tax owed and interest.
Payment Options and Support
Taxpayers can pay through the HMRC app or GOV.UK portal using debit or credit cards, bank transfer, or direct debit. Those unable to pay in full are encouraged to set up a payment plan in advance to avoid enforcement measures. Early payment reduces stress and prevents accumulation of extra charges.
HMRC’s Advice to Taxpayers
HMRC officials advise filing early to avoid mistakes and reduce financial pressure. Myrtle Lloyd, Chief Customer Officer, recommends early submission combined with manageable payment plans to help taxpayers stay in control. Exchequer Secretary James Murray added that HMRC’s Transformation Roadmap aims to modernise tax services, making compliance easier and reducing errors for households and businesses.
Preparing Ahead of the Deadline
Filing well before January 31 provides more time to gather documents, verify calculations, and resolve any issues. Digital submission through the HMRC app is the fastest method and ensures secure processing. Planning in advance also allows for installment arrangements if the tax owed cannot be paid in full.
Impact on Taxpayers
Millions of taxpayers are affected each year, and awareness of deadlines is critical. Missing the January 31 cut-off not only results in automatic fines but can also complicate future tax interactions, including eligibility for benefits or adjustments in HMRC records. Staying informed and proactive helps prevent unnecessary costs.
Frequently Asked Questions (FAQ)
- Who must file a Self Assessment tax return?
Individuals who are self-employed, landlords, or have additional income beyond standard PAYE are required to submit a tax return. - What is the penalty for missing the January 31 deadline?
The initial penalty is £100, with further fines and interest applied if the delay continues. - How can I pay my Self Assessment tax?
Payments can be made through the HMRC app, GOV.UK portal, debit or credit card, bank transfer, or direct debit. - Can I set up a payment plan if I cannot pay in full?
Yes, HMRC encourages taxpayers to arrange a payment plan before enforcement actions are triggered. - How can I avoid penalties and interest?
Filing early, double-checking your return, and paying on time or arranging installments helps avoid fines and interest charges.
