Register for HMRC Self Assessment by 5 October 2025

Self assessment for online sellersSelf assessment for gig workersSelf assessment registration guideSelf assessment tax return UKMaking Tax Digital for Income TaxAvoid self assessment penaltiesRegister for self assessment UKSelf assessment for side hustlesSelf assessment for landlordsSelf assessment for self-employedUnique Taxpayer Reference (UTR)Self assessment deadline 5 OctoberHMRC self assessment registration
Written By Dwayne Barnett

Register for HMRC Self Assessment by 5 October 202

Essential Guide for Self-Employed, Landlords & Side Hustlers

HMRC Urges Self-Employed, Landlords, and Side Hustlers: Register for Self Assessment by 5 October to Secure Your UTR

As the landscape of work and income continues to evolve, HMRC is issuing a timely and urgent reminder to all self-employed individuals, landlords, gig workers, and those with side hustles: register for self assessment by the 5 October deadline to obtain your Unique Taxpayer Reference (UTR) – an essential step for anyone required to file a tax return for the first time for the 2024-25 tax year.

Who Needs to Register?

The 5 October deadline applies to anyone who earned untaxed income during the tax year ending 5 April 2025 and who has not previously completed a self assessment tax return. This includes:

  • Self-employed sole traders earning more than £1,000 (before expenses)

  • Landlords with rental income

  • Gig economy workers and those with side hustles

  • Online sellers (e.g., Vinted, eBay, Facebook Marketplace) earning over £1,000 from trading or services

  • Crypto investors with taxable gains

  • Individuals with significant savings interest (over £10,000)

  • Directors and business partners

  • Anyone with untaxed income, such as dividends, foreign income, or pension income over £2,500

With high interest rates, the popularity of side hustles, and the rise of online platforms, more people than ever are likely to be affected this year.

Why Is the UTR So Important?

The UTR is your gateway to the self assessment system. Without it, you cannot file your tax return online. Registering by 5 October ensures HMRC has time to issue your UTR before the tax return deadlines.

Key Deadlines to Remember

  • 5 October 2025: Register for self assessment if you need to file for the first time

  • 31 October 2025: Deadline for paper tax returns

  • 31 January 2026: Deadline for online tax returns and payment of any tax owed

If you are unsure whether you need to file a return, HMRC provides an online checking tool at gov.uk.

Special Cases and Additional Considerations

  • PAYE taxpayers with additional income (e.g., rental, dividends) may also need to register

  • High Income Child Benefit Charge (HICBC) applies if you or your partner’s income exceeds £60,000 and you claim child benefit

  • Voluntary Class 2 NICs: Self-employed individuals earning below £1,000 who wish to protect their state pension entitlement must also register

  • Pensioners: The 2025 winter fuel payment does not need to be included on the 2024-25 return; recovery for higher earners will occur in the following tax year

Preparing for the Future: Making Tax Digital (MTD) for Income Tax

From 6 April 2026, the first wave of sole traders and landlords with qualifying income over £50,000 will be required to use Making Tax Digital (MTD) for Income Tax. This will mean:

  • Keeping digital records

  • Using MTD-compatible software

  • Submitting quarterly summaries and a year-end update

With only six months to go before these changes begin, HMRC is urging eligible taxpayers to join the MTD pilot programme now to familiarise themselves with the new system. Accountants and tax agents can register clients via gov.uk.

Why the UTR Matters

The UTR is your personal identifier within the self assessment system. Without it, you cannot file your tax return online. Registering by 5 October ensures HMRC has sufficient time to issue your UTR before the filing deadlines.

Missed the Deadline? Here’s What to Do

If you miss the 5 October deadline, you should still register for self assessment as soon as possible. HMRC has confirmed that late registration is still possible, and genuine reasons for delay will be considered when assessing penalties. However, failure to notify HMRC of your chargeability on time can result in penalties, and you may be required to submit a paper tax return by 31 October 2025.

✅ Top Tips to Avoid Late Filing Penalties

  1. Register Early
    Do not wait until the last minute. Registering early ensures you receive your UTR in good time and can access HMRC’s online services without delay.

  2. Keep Accurate Records
    Maintain detailed records of all income and expenses throughout the year. This will make completing your return easier and reduce the risk of errors.

  3. Use HMRC’s Online Tools
    Unsure if you need to file? Use HMRC’s online checker to confirm your obligations.

  4. Set Reminders for Key Deadlines

    • 5 October 2025: Register for self assessment

    • 31 October 2025: Paper return deadline

    • 31 January 2026: Online return and payment deadline

  5. File Even If You Cannot Pay
    Submit your return on time even if you cannot pay your tax bill in full. This avoids late filing penalties and allows you to arrange a payment plan with HMRC.

  6. Notify HMRC of Changes
    If you no longer need to file a return or have ceased self-employment, inform HMRC promptly to avoid unnecessary penalties.

  7. Seek Professional Advice
    If in doubt, consult a qualified accountant. At Barnett & Co, we can help you determine your obligations and ensure your return is accurate and timely.

HMRC guidance

Check how to register for self assessment

Self assessment tax returns

HMRC online checking tool to see if need to do self assessment

Sign up for Making Tax Digital for Income Tax

Dwayne Barnett
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