The 2017-18 tax return deadline for taxpayers using a paper self-assessment return is 31 October 2018. Late submission of a self-assessment return will become liable to a £100 late filing penalty. The penalty usually applies even if there is no liability or if any tax due is paid in full by 31 January 2019.
There are many advantages to filing online that include an extra three months (until 31 January 2019) in which to submit a return and pay any taxes due. Taxpayers also receive instant confirmation that a return has been filed and do not need to rely on the vagaries of the postal system. Any taxpayer due a refund will usually receive a quicker repayment when they file online.
Taxpayers with certain underpayments in the 2017-18 tax year can elect to have this amount collected via their tax code (in 2019-20), provided they are in employment or in receipt of a UK-based pension. The coding applies to certain debts and the amount of debt that can be coded out ranges from £3,000 to £17,000 based on a graduated scale. The maximum coding out allowance only applies to taxpayers with earnings exceeding £90,000.
Daily penalties of £10 per day will also take effect if the tax return is still outstanding three months after the filing date up to a maximum of £900. If the return still remains outstanding further higher penalties will be charged from six months and twelve months late.
Taxpayers that received a letter informing them that they have to submit a paper return after 30 July 2018 have an extended deadline which runs for three months from the date they received the letter to submit a paper return.