Self Assessment Tax Return 2018-19

If you received untaxed income (e.g. self employed earnings or rental income from property) between 6 April 2018 and 5 April 2019 you’ll need to file a Self Assessment Tax Return. The deadline for online filing of your 2018-19 Tax Return is Midnight 31 January 2020. The same deadline applies for paying any tax you owe for that period.

HMRC will issue a penalty of £100 if your Tax Return is up to 3 months late. You’ll have to pay more if you file later, or if you pay your tax bill late. You’ll also be charged interest on late payments.

Register for Self Assessment

If you’ve never submitted a return before you’ll need to register for Self Assessment. There are different registration procedures that depend on whether you’re self-employed, in a partnership, or not self-employed but needing to declare income. Visit the Gov.UK website to find out more and register for Self Assessment.

Notice to complete a Self Assessment Tax Return
Notice to complete a tax return

Filing your return

Once you have registered, you’ll receive your Unique Taxpayer Reference (UTR) in a letter. Follow the instructions in the letter to set up a Government Gateway account.

When you sign in to file your Self Assessment Tax Return you’ll need your UTR. You’ll be asked to prove your identity using Government Gateway or GOV.UK Verify. 

Supporting documents

To complete your 2018-19 tax return you’ll need details of your income and expenses for the period. Relevant documents will include any or all of the following:

If you’re employed or you left a job

  • P60 – this form will show your pay and tax for the tax year.
  • P11D- this form will show any expenses and benefits – such as a company car or health insurance – that you received in the tax year.
  • Details of any benefits you’ve received as an employee shareholder.
  • Expense records if you’ve had to pay for things like tools, travel or specialist clothing for work.
  • P45 – this form will show your pay and tax to the date you left your job.
  • Letters informing you about any redundancy or termination payment.
  • Documents relating to Statutory Sick Pay, Statutory Maternity/ Paternity/ Adoption Pay, Universal Credit, and other Social Security payments.

If you’re self employed

  • Records of sales, business expenses, VAT, PAYE, and other documents relating to your business if self employed (you’ll will need these calculate your taxable profit for the year)
  • Records of dividends vouchers received from UK companies
  • Records of any money you borrow from or pay into your own limited company (i.e. ‘director’s loan account’)

If you have savings, investments and pensions

  • Bank or building society statements and passbooks, statements of interest and income, insurance policies, any other documents relating to any other savings, investments and pensions
  • Details of rental income received and allowable expenses you paid to run your property
  • receipts, bills and invoices relating to the sale or disposal of any assets that may be subject to Capital Gains Tax.

If you worked abroad

  • Evidence of income from overseas – payslips, bank statements, payment confirmations, dividend certificates from overseas companies, for example.
  • Receipts for any overseas expenses you want to claim to reduce your tax bill.
  • Certificates and other proof of the tax you’ve already paid either in the UK or overseas.

The above list of supporting documents is by no means exhaustive. Filing your tax return will be much easier if you have relevant documents to hand, and you should start gathering and organising them as soon as possible.  

Related article – Bookkeeping Tips For New Business Owners

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