Self Assessment Tax Return

Need a hand with your Self Assessment tax return?

How can we help?

  • Register with HMRC
  • Prepare and submit your tax returns
  • Estimate tax bills
  • Evidence earnings for mortgage applications
  • Deal with HMRC on your behalf
What information do I need to provide?

Self Assessment is a system HM Revenue and Customs uses to collect Income Tax.

Tax is usually deducted automatically from wages, pensions and savings. People and businesses with other income must report it in a tax return.

We can deal with HMRC on your behalf & help with your self-assessment tax returns. In most cases, you won't even need to step a foot into our office, as we are a predominantly paperless company we can process your return online through our client portal.

Get in touch with us today - Contact Us


For 2020/21 Tax Returns the deadline has now passed.

  • For 2021/22 Tax Returns, the period started on 6th April 2021 and ended on 5th April 2022 and you must register for self-assessment before 5th October 2022.
  • Paper returns are due by 31st October 2022.
  • Online returns are due by 31st January 2023.
  • Any tax owed in the 2021/22 period is also due by 31st January 2023.
  • There’s an additional payment deadline of 31 July if you make advance payments towards your bill (known as ‘payments on account’).

Partnership Returns

If your partnership’s accounting date is between 1 February and 5 April and one of your partners is a limited company, the deadline for:

  • online returns is 12 months from the accounting date
  • paper returns is 9 months from the accounting date


You’ll get a penalty if you need to send a tax return and you miss the deadline for submitting it or paying your bill.

You’ll get a penalty of £100 if your tax return is up to 3 months late. You’ll have to pay more if it’s later, or if you pay your tax bill late. You’ll also be charged interest on late payments.

You can appeal against a penalty if you have a reasonable excuse.

Frequently Asked Questions

Q: How to get my UTR number?

A: Your UTR is a Unique Taxpayer Reference that you get when you register as self-employed. It consists of ten digits (sometimes with a letter K at its end) and is issued to you by HMRC.

If you have registered for self-assessment in the past with HMRC you can find your UTR number:

  1. On the front page of previous your tax returns
  2. On any Self Assessment documents, HMRC has sent you such as notices to file a return and payment reminders
  3. In your online government gateway account under the "self-assessment" section.

You can get it by registering for self-assessment at HMRC. The process consists of 4 key steps.

Before you start make sure you have your National Insurance number to hand.

  1. Register for HMRC's online service at the Government Gateway
  2. Then use the service to enrol for self-assessment
  3. After enrollment HMRC will send your UTR activation code in the post
  4. Activate your UTR number online using the activation code.

HMRC says your UTR activation code will arrive via post within 8 weeks. In our experience, it happens much faster. It is important to remember that once you have the code you have 28 days to use it for UTR activation.

Q: Can I be both employed and self-employed?

A: Yes!
You may need to register as a sole trader or if you work for a company you may need to check that you are paying the correct amount of tax. 
If you own your own business you are actually both an owner
("shareholder") and employee of your own company ("director"), but not self-employed
Please see our Annual Financial Accounts page for more information.

Q: What are the most common self-assessment mistakes?

  1. Forgetting about deadlines
  2. Forgetting about tax relief
  3. Forgetting about payments on account
  4. Getting your tax code wrong
  5. Forgetting to declare salary, benefits, and reimbursements from PAYE

Q: What is a tax code?

A: The tax code is just a series of numbers and letters that tells HMRC how much tax you should be paying. 

The numbers in your tax code tell your employer or pension provider how much tax-free income you are entitled to in that tax year. 

  • L: You're getting the standard tax-free Personal Allowance. This is the most common one
  • M: 10% of your partner’s personal allowance goes to you
  • N: 10% of your personal allowance goes to your spouse
  • S: You’re using the Scottish rate of income tax
  • T: Other: your tax code includes other calculations
  • Y: You were born before 6 April 1938, and get a higher personal allowance
  • 0T: Your personal allowance has been used up or you’ve started a new job
  • BR: You’re getting the basic rate
  • D0: You’re getting the higher rate
  • D1: You’re getting the additional rate
  • NT: You’re not paying tax on this income
  • K: You have income that isn’t being taxed another way and it’s worth more than your tax-free allowance

When you see BR, D0, or D1. It means that you're getting zero Personal Allowance. If you're on any of these codes and it's not from a second job, contact HMRC.

If you've just moved jobs. Make sure that you’re not on an emergency code.

The most common code for 2022/23 will be 1257L:

  • 1257 because the allowance in 2022/23 is £12,570
  • L for the standard personal allowance.

What they say

Martin gives a very personal and exceptional service. Always at the end of the phone to help with any questions I may have.  Martin is very knowledgeable, professional and approachable.  I would fully recommend his services to anyone.          

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