HMRC has published a news release to remind taxpayers that there is now less than 100 days to file their 2017-18 tax return. Last year over 11 million taxpayers completed a 2016-17 self assessment tax return, with 10.7 million of these taxpayers doing so on time.The deadline for submitting 2017-18 self assessment tax returns online is 31 January 2019. Taxpayers should also be aware that payment of any tax due should also be made by this date. This includes both the payment of any balance of self assessment liability for the 2017-18, plus any payment on account due for the current 2018-19 tax year.Any taxpayers that are filing online for the first time should ensure that they register to use HMRC’s self assessment online service as soon as possible. Once registered it can take up to seven working days for an activation code to be sent by mail. All filings should now be made online as the deadline for submitting paper returns for 2017-18 expired on 31 October 2018. There are penalties for late self assessment returns including an automatic £100 penalty for submitting a late return even if there was no tax to pay or the tax due was paid on time. Over 4.8 million taxpayers waited until January 2018 to file their 2016-17 tax return with over 750,000 waiting until the final day of 31 January. HMRC is encouraging taxpayers to complete their tax return as early as possible to avoid working during the upcoming holiday period or getting more stressed as the 31 January 2019 filing date looms.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 deadline to apply to have tax collected through your tax code is 30 December 2018.