UK Financial Calendar 2026/27 — Key Tax Dates and Deadlines

Q: When does the UK tax year start and end?

The UK tax year runs from 6 April to 5 April the following year. For example, the 2025/26 tax year runs from 6 April 2025 to 5 April 2026. The tax year end on 5 April is one of the most important financial dates for ISA contributions, pension carry-forward, Self Assessment returns, and any actions that are tied to the current tax year. The unusual 6 April start date dates back to calendar reforms in 1752.

Q: What is the Self Assessment deadline for 2025/26?

For the 2025/26 tax year (ending 5 April 2026), the key Self Assessment deadlines are: 5 October 2026 — register for Self Assessment if new to filing; 31 October 2026 — paper tax return deadline; 31 January 2027 — online tax return deadline and payment of any tax owed. Missing the 31 January deadline incurs an automatic £100 penalty plus interest on unpaid tax. A further £10/day penalty applies after 3 months.

Q: When is the ISA deadline?

The ISA deadline is 5 April each year — the end of the tax year. Unused ISA allowance (£20,000 per year for adults, £9,000 for Junior ISAs) cannot be carried forward to the next tax year. You must make contributions by midnight on 5 April to use the current year's allowance. Cash ISAs, Stocks and Shares ISAs, Innovative Finance ISAs and Lifetime ISAs all share the £20,000 annual allowance.

Q: What is pension carry-forward and when can I use it?

Pension carry-forward allows you to use unused annual pension allowance from the three preceding tax years. The standard annual allowance is £60,000 (or 100% of earnings, whichever is lower). If you did not use your full allowance in 2022/23, 2023/24 or 2024/25, you can carry that unused amount forward and contribute more than £60,000 in 2025/26. You must have been a member of a registered pension scheme in the year you're carrying forward from. Three-year carry-forward years expire at the end of each tax year — so 2022/23 carry-forward expires on 5 April 2026.

Q: When do employers have to issue P60s?

Employers must issue P60 forms to all employees who were employed on 5 April (the last day of the tax year) by 31 May each year. So for the 2025/26 tax year, P60s must be issued by 31 May 2026. A P60 summarises total pay and deductions (Income Tax, National Insurance, student loan repayments) for the tax year. You need your P60 to complete a Self Assessment tax return or to check your tax.

Q: What are the VAT return deadlines?

VAT returns are typically filed quarterly, one month and 7 days after the end of each VAT quarter. For example, if your VAT quarter ends 31 March, your return and payment are due by 7 May. Common quarterly VAT periods end on: 31 March/30 June/30 September/31 December (Group 1), 30 April/31 July/31 October/31 January (Group 2), or 31 May/31 August/30 November/28 February (Group 3). Annual VAT accounting scheme businesses have one annual return due 2 months after their year end.

Q: When do companies have to file accounts and pay Corporation Tax?

For a limited company with a 31 December year end: Corporation Tax payment is due 9 months and 1 day after year end (i.e. 1 October the following year for small companies). Company accounts must be filed with Companies House within 9 months of year end (30 September). The Corporation Tax return (CT600) must be filed with HMRC within 12 months of year end (31 December). Large companies (profits over £1.5 million) pay Corporation Tax in quarterly instalments.

Q: What is Making Tax Digital (MTD) and when does it apply?

Making Tax Digital for Income Tax Self Assessment (MTD ITSA) is being phased in from April 2026. Self-employed individuals and landlords with income over £50,000 must comply from April 2026. Those with income over £30,000 must comply from April 2027. Those over £20,000 from April 2028. MTD ITSA requires quarterly digital submissions of income and expenses to HMRC via approved software, replacing the annual Self Assessment return for affected taxpayers. Partnerships will be brought in at a later date.

Last updated: 25 May 2026How we verify

The UK financial year runs from 6 April to 5 April. Missing key deadlines can mean automatic penalties, lost tax-free allowances or unnecessary interest charges. This calendar covers all major tax and financial deadlines for the 2025/26 and 2026/27 tax years.

The UK Tax Year at a Glance

6 April

Tax year starts

New allowances reset

5 April

Tax year ends

Use-it-or-lose-it deadlines

£20,000

ISA allowance

Per person, per year

The UK tax year starts on 6 April rather than 1 January due to a quirk of history: when Britain adopted the Gregorian calendar in 1752 (losing 11 days), the Treasury adjusted the tax year start to avoid losing revenue. The old New Year — 25 March (Lady Day) — shifted to 5 April under the old Julian calendar, then to 6 April in 1800 when another leap year correction was skipped.

Key Dates: 2025/26 Tax Year and Beyond

Tax yearSelf AssessmentPayrollNITaxMTD

5 April 2025

End of 2024/25 tax year — ISA deadline for 2024/25

Tax year

6 April 2025

Start of 2025/26 tax year — new ISA allowance begins

Tax year

6 April 2025

New National Insurance rates and thresholds take effect

6 April 2025

New Income Tax rates for Scotland take effect

Tax

31 May 2025

Employers must issue P60s for 2024/25 tax year

Payroll

6 July 2025

Deadline for employers to submit P11D forms for 2024/25 benefits

Payroll

31 July 2025

Second payment on account for 2024/25 Self Assessment

Self Assessment

1 August 2025

HMRC interest on overdue tax starts (at Bank Rate + 2.5%)

Tax

5 October 2025

Deadline to register for Self Assessment for 2024/25

Self Assessment

31 October 2025

Paper Self Assessment deadline for 2024/25

Self Assessment

30 December 2025

Online SA deadline if tax <£3,000 and want PAYE collection

Self Assessment

31 January 2026

Online Self Assessment deadline for 2024/25 and any tax payment

Self Assessment

31 January 2026

First payment on account for 2025/26 due

Self Assessment

5 April 2026

End of 2025/26 tax year — ISA deadline, pension carry-forward deadline (2022/23 carry-forward expires)

Tax year

6 April 2026

MTD ITSA mandatory for self-employed / landlords with income > £50,000

MTD

31 May 2026

P60 issue deadline for 2025/26 tax year

Payroll

31 July 2026

Second payment on account for 2025/26

Self Assessment

5 October 2026

Self Assessment

31 January 2027

Online Self Assessment deadline for 2025/26 and payment

Self Assessment

Red border = high importance / financial penalty risk. Amber border = medium importance.

Self Assessment Deadlines in Detail

Self Assessment affects the self-employed, landlords, higher-rate taxpayers, directors and anyone with income over £100,000. There are multiple deadlines across the year — missing any of them triggers automatic penalties.

Deadline	What it is	Penalty if missed
5 October	Register for Self Assessment (if new)	No direct penalty but may miss the filing deadline
31 October	Paper tax return deadline	£100 automatic penalty
31 January	Online return + all tax owed	£100 penalty + 5% interest on unpaid tax
31 January	1st payment on account (50% of prior year bill)	Interest from 1 February
31 July	2nd payment on account (50% of prior year bill)	Interest from 1 August
30 December	Online return to collect tax via PAYE (if < £3,000)	Lose option to pay via PAYE

Payments on account: If your Self Assessment tax bill exceeds £1,000, HMRC requires advance payments (payments on account) towards the following year's bill — each payment is 50% of the current year's liability. You can apply to reduce payments on account if you expect a lower bill.

Payroll and Employer Deadlines

Date	Employer obligation
Each payday	Submit Full Payment Submission (FPS) to HMRC via RTI
19th of month	Pay PAYE/NI to HMRC (cheque); 22nd if paying electronically
5 April	Final payroll submission (FPS or EPS) for the tax year
31 May	Issue P60s to all employees employed on 5 April
6 July	Submit P11D forms for benefits in kind
19 July	Pay Class 1A NI on benefits in kind
By 6 April	Notify any changes to payroll — new starters, leavers, tax codes

VAT Return Deadlines

VAT-registered businesses (registration threshold: £90,000 turnover) file quarterly VAT returns. Returns and payment are due one calendar month and 7 days after the end of each quarter. Most businesses are in one of three stagger groups:

Stagger group	Quarter ends	Return and payment due
Group 1 (March)	31 Mar / 30 Jun / 30 Sep / 31 Dec	7 May / 7 Aug / 7 Nov / 7 Feb
Group 2 (April)	30 Apr / 31 Jul / 31 Oct / 31 Jan	7 Jun / 7 Sep / 7 Dec / 7 Mar
Group 3 (May)	31 May / 31 Aug / 30 Nov / 28 Feb	7 Jul / 7 Oct / 7 Jan / 7 Apr

Annual Allowances That Reset on 6 April

These allowances cannot be carried forward — unused amounts are lost at midnight on 5 April each year.

Allowance	2025/26 amount	Notes
ISA (adult)	£20,000	Across all ISA types combined
Junior ISA (JISA)	£9,000	Per child
Lifetime ISA (LISA)	£4,000	Counts toward £20,000 limit
Capital Gains Tax annual exempt amount	£3,000	Reduced from £6,000 in 2023/24
Dividend allowance	£500	Reduced from £1,000 in 2023/24
Personal Savings Allowance (basic rate)	£1,000	Higher rate: £500; Additional rate: £0
Trading allowance	£1,000	For casual self-employment income
Property allowance	£1,000	For property income (not the same as rent-a-room)

Company Accounts and Corporation Tax

Limited companies have separate filing deadlines from personal tax. Filing obligations depend on your company's accounting year end rather than the personal tax year.

Filing obligation	Deadline	Filed with
Corporation Tax payment (small company)	9 months + 1 day after year end	HMRC
Annual accounts	9 months after year end	Companies House
Corporation Tax return (CT600)	12 months after year end	HMRC
Confirmation statement	Within 14 days of due date (annual)	Companies House
Large company CT (instalment 1)	6 months + 13 days into accounting period	HMRC

Frequently Asked Questions

When does the UK tax year start and end?

The UK tax year runs from 6 April to 5 April the following year. For example, the 2025/26 tax year runs from 6 April 2025 to 5 April 2026. The tax year end on 5 April is one of the most important financial dates for ISA contributions, pension carry-forward, Self Assessment returns, and any actions that are tied to the current tax year. The unusual 6 April start date dates back to calendar reforms in 1752.

What is the Self Assessment deadline for 2025/26?

For the 2025/26 tax year (ending 5 April 2026), the key Self Assessment deadlines are: 5 October 2026 — register for Self Assessment if new to filing; 31 October 2026 — paper tax return deadline; 31 January 2027 — online tax return deadline and payment of any tax owed. Missing the 31 January deadline incurs an automatic £100 penalty plus interest on unpaid tax. A further £10/day penalty applies after 3 months.

When is the ISA deadline?

The ISA deadline is 5 April each year — the end of the tax year. Unused ISA allowance (£20,000 per year for adults, £9,000 for Junior ISAs) cannot be carried forward to the next tax year. You must make contributions by midnight on 5 April to use the current year's allowance. Cash ISAs, Stocks and Shares ISAs, Innovative Finance ISAs and Lifetime ISAs all share the £20,000 annual allowance.

Show 5 more questions

What is pension carry-forward and when can I use it?

Pension carry-forward allows you to use unused annual pension allowance from the three preceding tax years. The standard annual allowance is £60,000 (or 100% of earnings, whichever is lower). If you did not use your full allowance in 2022/23, 2023/24 or 2024/25, you can carry that unused amount forward and contribute more than £60,000 in 2025/26. You must have been a member of a registered pension scheme in the year you're carrying forward from. Three-year carry-forward years expire at the end of each tax year — so 2022/23 carry-forward expires on 5 April 2026.

When do employers have to issue P60s?

Employers must issue P60 forms to all employees who were employed on 5 April (the last day of the tax year) by 31 May each year. So for the 2025/26 tax year, P60s must be issued by 31 May 2026. A P60 summarises total pay and deductions (Income Tax, National Insurance, student loan repayments) for the tax year. You need your P60 to complete a Self Assessment tax return or to check your tax.

What are the VAT return deadlines?

VAT returns are typically filed quarterly, one month and 7 days after the end of each VAT quarter. For example, if your VAT quarter ends 31 March, your return and payment are due by 7 May. Common quarterly VAT periods end on: 31 March/30 June/30 September/31 December (Group 1), 30 April/31 July/31 October/31 January (Group 2), or 31 May/31 August/30 November/28 February (Group 3). Annual VAT accounting scheme businesses have one annual return due 2 months after their year end.

When do companies have to file accounts and pay Corporation Tax?

For a limited company with a 31 December year end: Corporation Tax payment is due 9 months and 1 day after year end (i.e. 1 October the following year for small companies). Company accounts must be filed with Companies House within 9 months of year end (30 September). The Corporation Tax return (CT600) must be filed with HMRC within 12 months of year end (31 December). Large companies (profits over £1.5 million) pay Corporation Tax in quarterly instalments.

What is Making Tax Digital (MTD) and when does it apply?

Making Tax Digital for Income Tax Self Assessment (MTD ITSA) is being phased in from April 2026. Self-employed individuals and landlords with income over £50,000 must comply from April 2026. Those with income over £30,000 must comply from April 2027. Those over £20,000 from April 2028. MTD ITSA requires quarterly digital submissions of income and expenses to HMRC via approved software, replacing the annual Self Assessment return for affected taxpayers. Partnerships will be brought in at a later date.

Related Calculators

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About the author

James Morgan

Property & Mortgage Writer

James Morgan has been writing about UK property and mortgages since 2016. He covers the full purchase journey — affordability checks, mortgage product comparison, the deposit and loan-to-value puzzle, stamp duty (SDLT in England and Northern Ireland, LBTT in Scotland, LTT in Wales), first-time buyer reliefs, conveyancing costs, and what to expect at completion. James also writes on the landlord side: buy-to-let mortgages, the 3% additional-property SDLT surcharge, Section 24 finance-cost restriction, rental yield maths, and the practical realities of being a small private landlord in the post-2017 tax regime. He has a particular interest in the remortgage decision — when to switch product, the trade-off between rate and arrangement fee, early repayment charges, and how to read a mortgage offer document. James's mortgage worked examples are built up from the underlying amortisation schedule, not borrowed from comparison sites, and stamp-duty figures are verified band-by-band against the HMRC SDLT calculator. He writes to CalcHub's editorial standards, with primary-source citations to HMRC, Revenue Scotland and the Welsh Revenue Authority, and clear disclosure that CalcHub does not sell mortgages or take affiliate commission on regulated mortgage products.

Property journalist since 2016
UK mortgage and stamp-duty specialism (SDLT, LBTT, LTT)
Writes to CalcHub editorial standards (primary-source citation, annual review)

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UK Financial Calendar 2026/27 — Key Tax Dates and Deadlines

Last updated: 25 May 2026How we verify

The UK Tax Year at a Glance

6 April

Tax year starts

New allowances reset

5 April

Tax year ends

Use-it-or-lose-it deadlines

£20,000

ISA allowance

Per person, per year

Key Dates: 2025/26 Tax Year and Beyond

Tax yearSelf AssessmentPayrollNITaxMTD

5 April 2025

End of 2024/25 tax year — ISA deadline for 2024/25

Tax year

6 April 2025

Start of 2025/26 tax year — new ISA allowance begins

Tax year

6 April 2025

New National Insurance rates and thresholds take effect

6 April 2025

New Income Tax rates for Scotland take effect

Tax

31 May 2025

Employers must issue P60s for 2024/25 tax year

Payroll

6 July 2025

Deadline for employers to submit P11D forms for 2024/25 benefits

Payroll

31 July 2025

Second payment on account for 2024/25 Self Assessment

Self Assessment

1 August 2025

HMRC interest on overdue tax starts (at Bank Rate + 2.5%)

Tax

5 October 2025

Deadline to register for Self Assessment for 2024/25

Self Assessment

31 October 2025

Paper Self Assessment deadline for 2024/25

Self Assessment

30 December 2025

Online SA deadline if tax <£3,000 and want PAYE collection

Self Assessment

31 January 2026

Online Self Assessment deadline for 2024/25 and any tax payment

Self Assessment

31 January 2026

First payment on account for 2025/26 due

Self Assessment

5 April 2026

End of 2025/26 tax year — ISA deadline, pension carry-forward deadline (2022/23 carry-forward expires)

Tax year

6 April 2026

MTD ITSA mandatory for self-employed / landlords with income > £50,000

MTD

31 May 2026

P60 issue deadline for 2025/26 tax year

Payroll

31 July 2026

Second payment on account for 2025/26

Self Assessment

5 October 2026

Self Assessment

31 January 2027

Online Self Assessment deadline for 2025/26 and payment

Self Assessment

Red border = high importance / financial penalty risk. Amber border = medium importance.

Self Assessment Deadlines in Detail

Deadline	What it is	Penalty if missed
5 October	Register for Self Assessment (if new)	No direct penalty but may miss the filing deadline
31 October	Paper tax return deadline	£100 automatic penalty
31 January	Online return + all tax owed	£100 penalty + 5% interest on unpaid tax
31 January	1st payment on account (50% of prior year bill)	Interest from 1 February
31 July	2nd payment on account (50% of prior year bill)	Interest from 1 August
30 December	Online return to collect tax via PAYE (if < £3,000)	Lose option to pay via PAYE

Payroll and Employer Deadlines

Date	Employer obligation
Each payday	Submit Full Payment Submission (FPS) to HMRC via RTI
19th of month	Pay PAYE/NI to HMRC (cheque); 22nd if paying electronically
5 April	Final payroll submission (FPS or EPS) for the tax year
31 May	Issue P60s to all employees employed on 5 April
6 July	Submit P11D forms for benefits in kind
19 July	Pay Class 1A NI on benefits in kind
By 6 April	Notify any changes to payroll — new starters, leavers, tax codes

VAT Return Deadlines

Stagger group	Quarter ends	Return and payment due
Group 1 (March)	31 Mar / 30 Jun / 30 Sep / 31 Dec	7 May / 7 Aug / 7 Nov / 7 Feb
Group 2 (April)	30 Apr / 31 Jul / 31 Oct / 31 Jan	7 Jun / 7 Sep / 7 Dec / 7 Mar
Group 3 (May)	31 May / 31 Aug / 30 Nov / 28 Feb	7 Jul / 7 Oct / 7 Jan / 7 Apr

Annual Allowances That Reset on 6 April

These allowances cannot be carried forward — unused amounts are lost at midnight on 5 April each year.

Allowance	2025/26 amount	Notes
ISA (adult)	£20,000	Across all ISA types combined
Junior ISA (JISA)	£9,000	Per child
Lifetime ISA (LISA)	£4,000	Counts toward £20,000 limit
Capital Gains Tax annual exempt amount	£3,000	Reduced from £6,000 in 2023/24
Dividend allowance	£500	Reduced from £1,000 in 2023/24
Personal Savings Allowance (basic rate)	£1,000	Higher rate: £500; Additional rate: £0
Trading allowance	£1,000	For casual self-employment income
Property allowance	£1,000	For property income (not the same as rent-a-room)

Company Accounts and Corporation Tax

Limited companies have separate filing deadlines from personal tax. Filing obligations depend on your company's accounting year end rather than the personal tax year.

Filing obligation	Deadline	Filed with
Corporation Tax payment (small company)	9 months + 1 day after year end	HMRC
Annual accounts	9 months after year end	Companies House
Corporation Tax return (CT600)	12 months after year end	HMRC
Confirmation statement	Within 14 days of due date (annual)	Companies House
Large company CT (instalment 1)	6 months + 13 days into accounting period	HMRC