The 2018-19 tax return deadline for submitting your paper Self-Assessment returns is 31 October 2019. Late submission of a Self-Assessment return will trigger 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 2020.
If you are still submitting paper tax returns, we would recommend that you consider the benefits of submitting the returns electronically. This extends the filing deadline by an additional three months (until 31 January 2020). You will also benefit from quicker repayments of any tax refunds you may be due and instant confirmation that a return has been filed.
Daily penalties of £10 per day will take effect if your 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.
If you received a letter informing you to submit a paper return after 30 July 2019, then you have an extended deadline which runs for three months from the date you received the letter requesting you to submit a paper return.