Tax Diary September/October 2026

1 September 2026 – Due date for corporation tax due for the year ended 30 November 2025.

19 September 2026 – PAYE and NIC deductions due for month ended 5 September 2026. (If you pay your tax electronically the due date is 22 September 2026)

19 September 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 September 2026. 

19 September 2026 – CIS tax deducted for the month ended 5 September 2026 is payable by today.

1 October 2026 – Due date for Corporation Tax due for the year ended 31 December 2025.

19 October 2026 – PAYE and NIC deductions due for month ended 5 October 2026. (If you pay your tax electronically the due date is 22 October 2026)

19 October 2026 – Filing deadline for the CIS monthly return for the month ended 5 October 2026. 

19 October 2026 – CIS tax deducted for the month ended 5 October 2026 is payable by today.

31 October 2026 – Latest date you can file a paper version of your 2025-26 self-assessment tax return.

All Finance News

Received a P800 from HMRC?

HMRC is currently carrying out its annual reconciliation of PAYE for the 2025-26 tax year. Between June and November, HMRC calculates the Income Tax paid by individuals and checks whether the correct amount has been collected. Where HMRC identifies a difference, it may issue a tax calculation

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Summer VAT relief has ended

The temporary 5% reduced rate of VAT introduced for certain children’s meals, tickets and family attractions ended on 1 September 2026. The relief applied from 25 June 2026 and was intended to reduce the cost of selected activities and services for families during the summer holidays. The relief

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