How to Deregister From Self Assessment: Complete Step-by-Step Guide

What does deregistering from Self Assessment mean?

Deregistering from Self Assessment sometimes called stopping Self Assessment, cancelling Self Assessment, or closing your Self Assessment account is the formal process of notifying HMRC that you no longer need to file an annual Self Assessment tax return.

It does not mean your tax records are deleted. HMRC keeps your records for a minimum of six years. It simply means HMRC will no longer expect a tax return from you each year and will not issue penalties if you do not file one.

This matters more than most people realise. If you stop filing without officially notifying HMRC, they will continue to send you reminders, chase you for returns you haven’t submitted, and eventually issue automatic £100 late-filing penalties even if you owe no tax. Deregistering correctly stops all of that.

Important
Simply stopping sending tax returns is not enough. You must actively tell HMRC you no longer need to file. Failing to do so leads to automatic penalties and debt collection letters regardless of whether you owe any tax.

Who can deregister from Self Assessment?

You may be eligible to deregister from Self Assessment if your circumstances have changed so that you no longer meet the criteria that required you to register in the first place. HMRC sets specific eligibility conditions.

You CAN deregister if

1. You have stopped being self-employed and have no other untaxed income
2. Your self-employment income has fallen below the £1,000 trading allowance
3. You have moved back into full-time PAYE employment
4. You have closed a business partnership
5. You no longer receive rental income above the tax threshold
6. You no longer receive untaxed investment income (dividends, savings)
7. You no longer need to pay the High Income Child Benefit Charge
8. You were filing voluntarily and wish to stop

You CANNOT deregister if

1. You are still self-employed with income above £1,000 per year
2. You still have untaxed rental income above the property allowance
3. You still receive income from savings or dividends above the tax-free allowances
4. You are a company director (directors generally must file annually)
5. You earn over £150,000 from PAYE employment
6. You have outstanding, unfiled tax returns from previous years
7. You have outstanding tax, interest, or penalties owed to HMRC

Before you contact HMRC
Confirm you have submitted your final tax return for the last year you were required to file, and that all outstanding tax has been paid. HMRC will not process a deregistration request if you have unresolved balances.

How to deregister from Self Assessment: Step-by-Step Guide

There are three routes to deregister from Self Assessment: online through the Government Gateway (fastest), by phone, or by post. The online method is strongly recommended as it is processed most quickly and provides an immediate reference number.

Confirm your eligibility

Before contacting HMRC, verify that you genuinely no longer need to file a Self Assessment return. Review the criteria in the section above. If you are unsure, call HMRC’s Self Assessment helpline on 0300 200 3310 (Mon–Fri, 8am–6pm) for guidance before you start.

File any outstanding tax returns first

HMRC will not deregister you if you have unfiled returns. Check your account and make sure every required tax return has been submitted including the final one for the year your circumstances changed. You cannot skip this step.

Pay all outstanding tax, penalties, and interest

Clear any outstanding balance on your Self Assessment account before applying to deregister. If you cannot pay in full, contact HMRC to arrange a Time to Pay arrangement but note that HMRC may not complete deregistration until all debts are resolved.

Contact HMRC to deregister

Choose your preferred method:

• Online: Log in to your Government Gateway account → Self Assessment → stop or cancel your return (see detailed steps below)
• Phone: Call 0300 200 3310 (Mon–Fri, 8am–6pm). Have your UTR and National Insurance number ready. Lines are quietest before 10am.
• Post: Write to HMRC Self Assessment, HM Revenue and Customs, BX9 1AS. Include your full name, UTR, National Insurance number, the date you stopped, and the reason for deregistration.

Wait for HMRC’s written confirmation

HMRC will write to you typically within 3 to 4 weeks confirming that your Self Assessment registration has been cancelled. Keep this letter. It is your proof that you are no longer required to file, which protects you from any future penalty notices.

Keep your business records for 5 years

Even after deregistering, HMRC can enquire into your previous returns for up to 5 years from the date you submitted your final return (or longer if they suspect irregularities). Keep all financial records bank statements, invoices, receipts, and tax return copies for this full period.

How to Deregister for Self Assessment Online

Deregistering online via the Government Gateway is the quickest and most efficient method. The form takes around 10 minutes to complete. Here is the exact process:

If you are stopping because you are no longer self-employed

1. Go to gov.uk and search for ‘stop being self-employed’
2. Select the link: “Tell HMRC you’ve stopped being self-employed”
3. Sign in to your Government Gateway account using your User ID and password
4. Select “Tell HMRC you’re stopping self-employment” from the options presented
5. Enter the date you stopped being self-employed — note that HMRC cannot accept a date earlier than seven days before the date you ceased trading
6. Confirm your National Insurance number and contact details
7. Submit the form. Note your reference number on screen.

If you are stopping for a different reason (e.g. income dropped below threshold)

1. Log in to your Government Gateway account at gov.uk/log-in-file-self-assessment-tax-return
2. Navigate to Self Assessment from your account home page
3. Look for the option: “Check if you need to send a Self Assessment tax return” or “Stop Self Assessment”
4. Follow the on-screen prompts, explaining your changed circumstances
5. Submit. HMRC will review and confirm in writing.

What you need before you start
Your Government Gateway User ID and password · Your Unique Taxpayer Reference (UTR) a 10-digit number on previous tax returns or HMRC correspondence · Your National Insurance number · The exact date your circumstances changed or you stopped trading.

Stopping Self-Employment: Additional Steps

If you are deregistering because you have stopped being self-employed rather than just reducing income there are several additional steps to take alongside the Self Assessment deregistration itself.

If you were VAT registered

VAT registration must be cancelled separately. Go to gov.uk and search ‘cancel VAT registration’ to find the online form. You cannot cancel your VAT registration through the same process as your Self Assessment. If you deregister from Self Assessment but leave VAT registration open, you will continue to be liable for quarterly VAT returns and any associated penalties.

If you had employees (PAYE scheme)

If you employed staff, you must close your PAYE scheme separately and submit a final Full Payment Submission (FPS) or Employer Payment Summary (EPS) to HMRC. Notify HMRC as soon as you stop employing people. Leaving a PAYE scheme open will continue generating reporting obligations.

If you were registered under the Construction Industry Scheme (CIS)

CIS registration is managed entirely separately from Self Assessment. Call the CIS helpline on 0300 200 3210 (Mon–Fri, 8am–6pm) to notify them you have stopped operating as a contractor or subcontractor. You cannot deregister from CIS online.

Moving back into PAYE employment

If you are returning to employed work, be aware that when you stop being self-employed, HMRC does not generate a P45 for you. Instead, give your new employer a Starter Checklist (which replaced the old P46 form). This allows your employer to assign the correct tax code so you do not overpay or underpay tax in your new role.

Filing your final Self Assessment Tax Return

One of the most commonly misunderstood aspects of deregistering from Self Assessment is that you must still file a final tax return for the last year you were required to file. Submitting your deregistration request does not exempt you from this final return.

What to include in your final return

• All self-employment income from the start of the tax year until the date you stopped trading
• Any employment income received in the same tax year (if you moved to PAYE employment partway through the year)
• Allowable business expenses up to your cessation date
• Capital allowances on any business assets disposed of when you ceased trading
• Any income from savings, dividends, or property if applicable

Deadlines for your final return

Your final return follows the standard Self Assessment deadlines. For the 2025/26 tax year (ending 5 April 2026), the deadlines are:
5 October 2026 — Registration deadline
If this is your first (or final) return and you haven’t yet registered, 5 October 2026 is the deadline to notify HMRC.
31 October 2026 — Paper return deadline
If filing your final return on paper, it must reach HMRC by this date.

31 January 2027 — Online return and payment deadline
Online returns and all outstanding tax must be submitted and paid by this date. This is also when any Payments on Account would be due though if you have deregistered and your income has ceased, you may be able to reduce these. Speak to an accountant.

What happens to your Self Assessment account after deregistering?

Many people worry about what happens to their tax records once they have stopped Self Assessment. Here is a clear breakdown:

Your records are not deleted

HMRC retains your previous tax returns, payment history, and Self Assessment records for a minimum of six years after the date of deregistration. You can still view historical returns via your Government Gateway account after deregistering.

You will stop receiving SA reminders

Once deregistered, HMRC will remove you from the mailing list for Self Assessment reminders, penalty notices, and filing deadline letters. This is one of the most immediately noticeable effects of successful deregistration.

Your UTR remains valid

Your Unique Taxpayer Reference (UTR) is a permanent number attached to your National Insurance record. It does not expire or become void when you deregister from Self Assessment. If you become self-employed again in the future, you will use the same UTR when re-registering.

You can re-register at any time

Deregistering from Self Assessment is not permanent. If your circumstances change again for example, you start a business, receive rental income, or begin receiving dividends above the allowance you simply re-register with HMRC using your original UTR. You must do this by 5 October following the end of the tax year in which you started receiving untaxed income.

Penalties for not deregistering or deregistering incorrectly

Failing to properly deregister from Self Assessment when you are no longer required to file carries genuine financial risk. HMRC’s automated system will continue to issue penalty notices regardless of whether you owe any tax.

Late filing penalties (if you fail to deregister)

• Day 1 after the deadline: Automatic £100 penalty — issued even if no tax is owed
• 3 months late: £10 per day, up to a maximum of £900
• 6 months late: Either £300 or 5% of the tax owed — whichever is greater
• 12 months late: A further £300 or 5% of tax owed — in serious cases HMRC can charge up to 100% of the tax due

How to appeal an HMRC penalty if you were not properly deregistered

If you have already received a penalty because you did not realise you needed to formally deregister, you can appeal using a “reasonable excuse” for example, that you genuinely believed your obligation had ended when you stopped trading. Contact HMRC’s Self Assessment helpline (0300 200 3310) or submit an appeal online through your Government Gateway account. The process is straightforward for first-time penalties where you have a clear reason.

How to Close your Self Assessment Account Completely

There is an important distinction between deregistering from Self Assessment (no longer needing to file annual returns) and closing your Government Gateway account (removing your HMRC online access entirely).

In almost all cases, you should not close your Government Gateway account, even after deregistering from Self Assessment. Your Government Gateway account gives you access to:

• Your National Insurance record and State Pension forecast
• PAYE tax codes and employment history
• Historical Self Assessment returns and payment records
• Any future HMRC correspondence
• Child Benefit claims and Personal Tax Account features

Keeping your Government Gateway login active costs nothing and gives you a valuable record of your entire tax history. Simply stop filing Self Assessment returns once HMRC has confirmed your deregistration in writing there is no need to go further.