Dates & Deadlines
21 September 2018
EC sales list
Deadline for online monthly or quarterly return filing.
Due date for payment of supplementary declarations for August 2018.
22 September 2018
Monthly electronic PAYE/class 1 NICs/student loan payment
If paying electronically, pay PAYE, class 1 NICs, student loan deductions and deductions from payments to subcontractors for the month up to the 5th of this month.
30 September 2018
Corporation tax return
Filing deadline for corporation tax return self-assessment form CT600 for period ended 30 September 2017 to be submitted to HMRC.
Disclosing undeclared offshore tax liabilities
Deadline for disclosing undeclared offshore tax liabilities (relating to income tax, capital gains tax or inheritance tax for the relevant periods) to HMRC is on or before 30 September 2018.
End of CT61 quarterly period.
Company accounts filing deadline
Deadline for filing your company tax return is 12 months after your accounting period for corporation tax ends.
01 October 2018
Corporation tax payment
Corporation tax payment due for year end 31 December 2017, for those companies not liable to pay their liability by instalments.
05 October 2018
Income tax and capital gains
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.
07 October 2018
Due date for August VAT returns unless exempted.