Deadline for online submission of self-assessment tax returns for tax year ended 5 April 2018 for HMRC to collect tax through PAYE codes, where they owe less than £3,000. Residence nil-rate band increases from £150,000 to £175,000. Taxpayers who do not receive a self-assessment tax return to complete must notify HMRC by 5 October if they had income or capital gains in the previous tax year on which further tax is due. Deadline for paper submission of self-assessment tax return for tax year ended 5 April 2018. New fuel rates come into force.