There are a number of reasons why a taxpayer needs to complete a Self Assessment return. This includes if they are self-employed, a company director, have an annual income over £100,000 and / or have income from savings, investment or property.Taxpayers that need to complete a Self Assessment return for the first time should inform HMRC as soon as possible. The latest date that HMRC should be notified is by 5 October following the end of the tax year for which a Self Assessment return needs to be filed. In certain circumstances HMRC will request taxpayers to complete tax returns. HMRC has an online tool that can help taxpayers ascertain whether they are required to submit a Self Assessment return. HMRC publishes a list of taxpayers who would usually be required to submit a Self Assessment return. The list includes: The self-employed; Taxpayers who had £2,500 or more in untaxed income; Those with savings or investment income of £10,000 or more before tax; Taxpayers who made profits from selling things like shares, a second home or other chargeable assets and need to pay Capital Gains Tax;Company directors – unless it was for a non-profit organisation (such as a charity) and you didn’t get any pay or benefits, like a company car;Taxpayers whose income (or that of their partner’s) was over £50,000 and one of you claimed Child Benefit;Taxpayers who had income from abroad that they needed to pay tax on; Taxpayers who lived abroad and had a UK income; Those whose income was over £100,000.