31 January 2018
Deadline for 1st payment on account for 2017/18 tax year.
5 April 2018
Deadline for claiming tax overpaid for the 2013/14 tax year under Self-Assessment
6 April 2018
First day of the new tax year 2018/19.
31 May 2018
Last date to give employees a form P60 for 2017/18.
6 July 2018
Copies of 2017/18 P11d documents issued to employees.
31 July 2018
Deadline for 2nd payment on account for tax year ending 5 April 2018.
5 October 2018
Deadline to register with the HMRC if you became self-employed or started receiving income from property.
31 October 2018
Deadline for paper Self-Assessment Returns for 2017/18 tax year.
30 December 2018
Deadline for online submission of Self-Assessment Returns for year ending 5 April 2018 for HMRC to collect tax through PAYE tax codes where they owe less than £3,000.
31 January 2019
Deadline for online self-assessment tax returns for 2017/18 tax year.
Deadline for paying tax bill for tax year ending 5 April 2018.
5 April 2019
End of tax year 2018/19.