Tax Deadlines
Never miss an HMRC deadline
MTD Quarterly Update Deadline 7 August 2026: Your First Submission, What's In It, and the Penalties
The first Making Tax Digital for Income Tax quarterly update is due 7 August 2026, covering 6 April to 5 July. What the update contains, why it's cumulative, the £200 penalty rules, and all four deadlines for 2026/27.
P11D Deadline 6 July 2026: What to File, Class 1A Dates, and the Penalties
P11D and P11D(b) forms for 2025/26 are due by 6 July 2026, with Class 1A NIC payable by 22 July. What counts as a benefit, exact penalties for missing it, and why this is one of the last P11D rounds ever.
CT600 Late Filing Penalties 2026: From £100 to £10,000+ Explained
Every CT600 late filing penalty HMRC charges in 2026/27. Day-one £100, three-month £100, six-month tax-based, twelve-month tax-based plus interest, appeals and reasonable excuses.
Quarterly Estimated Tax: Avoiding the IRS Underpayment Penalty
How to calculate and pay US quarterly estimated tax without underpayment penalties: safe harbor rules, the four 'quarters', Form 1040-ES, IRS Direct Pay and EFTPS.
Missed a Tax Deadline in the UK? Here's Exactly What to Do (2026)
Missed an HMRC or Companies House deadline? Act immediately — penalties escalate daily. This guide covers 2025/26 penalty rates for Self Assessment, VAT, Corporation Tax and annual accounts, plus how to appeal, claim reasonable excuse, and set up a payment plan.
Year-End Tax Planning for Limited Companies: 15 Ways to Reduce Your Tax Bill
Essential year-end tax planning strategies for UK limited company directors. Reduce Corporation Tax and maximise take-home before your year-end.
UK Self Assessment Deadlines 2025/26: Complete Guide
Never miss a self-assessment deadline. Complete guide to 2025/26 tax year filing dates, penalties, and how to stay compliant with HMRC.
When Is Corporation Tax Due? UK Deadlines, Rates and Penalties 2026/27
Corporation tax is due 9 months and 1 day after your year-end; the CT600 within 12 months. Full 2026/27 deadline tables, payment methods, instalment rules, and every penalty HMRC charges.
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