1 October 2026 Corporation Tax payment due for year ending 31 December 2025 Tax
5 October 2026 Deadline to register for Self-Assessment Tax
19 October 2026 PAYE postal submission deadline Tax
22 October 2026 PAYE electronic payment deadline Tax
22 October 2026 Electronic remittance to HMRC Tax
31 October 2026 Paper Self-Assessment tax return deadline (2025/26) Tax