Self Assessment Quick Links:

Do I need to Submit a Self Assessment?

Step 1: Organize Self Assessment Documents

Step 2: Register for Your Self Assessment

Step 3 – Fill In The Online Self-Assessment Form

Step 4 – Pay Your Self Assessment

If you’re a UK resident, you will know that the deadline for Self Assessments is around the corner. This might seem daunting to many, but it’s okay. We’re here to help you through it, step by step!

Do I Need to Complete A Self Assessment?

A lot of individuals in the UK need to submit a self-assessment.

If you are employed by a company and pay tax at source (i.e. your company is doing your PAYE – Pay As You Earn monthly) you do not need to submit a self assessment UNLESS you earn over  £100,000 annually (£8333.33 monthly). 

If you are earning an income which you have not paid tax on, you need to complete a self-assessment. This includes, but are not limited to:

Now that you know whether or not this is something you should be doing. Let’s take you through the steps to complete your Self-Assessment online:

Pre-planning prevents failure, right? So ensure that you are logging in with all the necessary documentation already compiled so you don’t have to scramble around trying to collect documents and information while you are attempting to submit everything. 

What will you need for your Self-Assessment? 

You will need the following documents and information to complete your online self-assessment: 

  • Your ten-digit Unique Taxpayer Reference (UTR)
  • Your National Insurance number
  • Details of your untaxed income from the tax year (including income from self-employment, dividends and interest on shares)
  • Records of any expenses relating to self-employment.
  • Any contributions to charity or pensions that might be eligible for tax relief (If applicable)

P60 or other records showing how much income you received that you’ve already paid tax on (via PAYE).

Do I need to submit a self assessment?

Step 2 - Register for Your Self-Assessment

If this is your first time doing a self-assessment, you will have to register for self-assessment on the

There are three categories of registration. 

If you are a sole proprietor and earning an income over £1000, you are required to registered for self assessment. 

Step 3 - Fill In The Online Self-Assessment Form

There are two sections in the self-assessment form. The first section (main section) deals with: 

  • Income (taxed and untaxed) in the form of dividends and interest.
  • Contributions to your Pension Fund
  • Donations made to charity.
  • Benefits (State Pension, Child Benefit and Blind Person’s Allowance).

The second section of the Self-Assessments mainly deals with any additional income that you have from being self-employed (SA103), property income (SA105) or declaring capital gains (SA108)

Remember that when you are filing as a self-employed individual, you can also claim tax relief. If your annual turnover is under £85,000 you can enter the lump sum of your total expenses without categorising or itemise your expenses. However, if your turnover is over £85,000 you are required to categorise each expense including a total at the bottom.  These expenses can include:

If you are claiming expenses it is important for you to keep a detailed record of all your expenses for up to 5 years.

Step 4 - Pay Your Self Assessment

When you’ve successfully submitted your self assessment, HMRC will notify you what your bill is (tax and national insurance if applicable). You can pay in whatever way is most comfortable for you. Some of the options available are: 

  • Online Banking.
  • CHAPS (Clearing House Automated Payment System).
  • Corporate Credit Card.
  • Debit Card.
  • At your Local Bank.
  • At your local building society.
  • Send a cheque.
  • Arrange Bank Transfer.
  • Direct Debit.

However, it is important to note the deadline (31 January). HMRC must have received the payment by the deadline, which means if you’re paying on the deadline or very close to the deadline it is recommended that you make use of instant payment methods to avoid penalties.

If you’re having trouble with your self assessment you can reach out to the CIGMA Accounting team.