When Are Taxes Due in the UK? 2026/27 Tax Deadlines Guide

Advising clients on exactly when are taxes due in the UK requires a comprehensive understanding of the specific revenue stream, the taxpayer’s trading structure, and the latest legislative changes. For the 2026/27 tax year, the government enforces strict deadlines across Income Tax, Capital Gains Tax, Corporation Tax, and VAT, underpinned by major new digital reporting mandates.

To establish the baseline for the 2026/27 tax year, Parliament has frozen the Personal Allowance at £12,570.  Section 2 of the Finance Act 2026 confirms the main rates of income tax remain at 20% (basic rate), 40% (higher rate), and 45% (additional rate).

Personal Income Tax (Self Assessment)

The traditional Self Assessment system operates on an annual cycle, but the deadlines vary depending on how you file and when you pay.

• Notifying HMRC: If you have untaxed income and are not already registered for Self Assessment, you must notify HMRC of your chargeability by 5 October following the end of the tax year.
• Filing a Paper Return: If you choose to submit a non-electronic paper return, you must deliver it to HMRC on or before 31 October following the tax year.
• Filing an Online Return: If you file electronically, HMRC grants you extra time; you must submit the return by 31 January following the end of the tax year.

When is the tax actually paid? Taxpayers generally pay their Income Tax through “payments on account” (advance instalments) and a final balancing payment.

• Payments on Account: You must pay these in two equal instalments on 31 January (in the year of assessment) and 31 July (after the year of assessment).  Each payment normally equals half of the previous year’s income tax and Class 4 NIC liability.
• Balancing Payment: You must settle any remaining income tax liability, alongside any Capital Gains Tax due, by the following 31 January.

Making Tax Digital for ITSA (The New Quarterly Deadlines)

From 6 April 2026, the tax deadline calendar changes fundamentally for sole traders and landlords earning a qualifying income over £50,000.  These taxpayers must sign up for Making Tax Digital for Income Tax Self Assessment (MTD for ITSA).

Under MTD, the law requires you to submit quarterly digital updates to HMRC via compatible software.  The standard quarterly deadlines for the 2026/27 tax year are:

• Quarter 1 (6 April to 5 July): Due by 7 August 2026.
• Quarter 2 (6 April to 5 October): Due by 7 November 2026.
• Quarter 3 (6 April to 5 January): Due by 7 February 2027.
• Quarter 4 (6 April to 5 April): Due by 7 May 2027.

Alternatively, taxpayers can elect to use “calendar update periods” (e.g., 1 April to 30 June), which align with the end of the month, though the final submission deadlines (7 August, 7 November, etc.) remain identical.

Capital Gains Tax on UK Residential Property

You do not report all tax annually. If you dispose of UK residential property, a strict 60-day reporting and payment window applies.

“The filing of a return in connection with a disposal of UK residential property, along with payment of any CGT falling due on the disposal, should be done within: 60 days of selling the property if the completion date was on or after 27 October 2021…”

Consequently, you must report the disposal and pay the Capital Gains Tax within 60 days of the completion date.  Furthermore, non-UK residents must report all UK property disposals within this 60-day window, regardless of whether any tax is actually due.

Corporation Tax

For companies, the deadlines for paying tax and filing the return do not align. For the financial year 2026, the main rate of Corporation Tax is 25%.

• Payment Deadline: A company must normally pay its Corporation Tax nine months and one day after the end of its accounting period.  For example, if a company’s accounting period ends on 31 December, the tax is due on 1 October the following year.
• Filing Deadline: The company has longer to file its actual return (the CT600). The statutory filing date is twelve months from the end of the accounting period.

2026 Penalty Increases: The government has tightened the penalty regime for companies that miss their filing deadlines. For Corporation Tax returns with a filing date on or after 1 April 2026, the fixed penalty for late filing increases from £100 to £200.  If the return is more than three months late, the penalty escalates from £200 to £400.

Value Added Tax (VAT)

If your business is VAT registered, you generally submit returns and make payments quarterly.

By default, the statutory deadline for submitting a VAT return and paying the tax is the last day of the month following the end of the return period.  However, HMRC provides a permanent extension for businesses that file and pay electronically. For online returns, HMRC extends the standard deadline by seven calendar days.

Therefore, if your VAT quarter ends on 30 June, your electronic return and cleared payment are due by 7 August.

Summary Table of Key Tax Deadlines

Next steps for research: Verify the exact mechanical steps required to submit a digital claim to reduce payments on account via approved MTD for ITSA software, and review the statutory appeal process for challenging the newly increased £200 Corporation Tax late filing penalties under reasonable excuse provisions.