Reference · 2026/27 Tax Year
UK Tax Calendar
Every key tax date in one place. Bookmark this page - missing these deadlines costs money. The tax year runs from 6 April to 5 April the following year.
2026/27 tax year (6 April 2026 - 5 April 2027). Always verify key deadlines at gov.uk as dates can change.
5 AprISA allowance deadline - unused allowance is lost forever at midnight
6 AprNew tax year begins - new ISA allowance, new CGT exemption, new annual cycle
31 JanOnline self-assessment deadline and payment deadline - penalties start immediately when late
April 2026Start of 2026/27 tax year
5
ISA deadline - last day of 2025/26ISA
Final day to use your 2025/26 ISA allowance. Unused allowance is permanently lost at midnight. JISA and LISA year-end timing matters here too.
6
New 2026/27 tax year beginsTax Year
New ISA, LISA and JISA allowance cycles begin. Use the current-year rates page alongside this calendar when checking any threshold-sensitive plan.
31
P60s must be issued by 31 MayPAYE
Employers must provide P60s to employees still in employment on 5 April by 31 May. Check it carefully - payroll errors do happen.
July 2026
6
P11D deadline for benefits in kindBenefits in Kind
Benefits such as company cars and private medical insurance should be reported by this point. If a benefit applies to you, check the figures and coding consequences.
31
Second payment on account for 2025/26Self-Assessment
This is the second advance payment toward your 2025/26 bill if payments on account apply to you. Late payment attracts interest immediately.
October 2026
5
Register for Self Assessment if 2025/26 was your first filing yearSelf-Assessment
If 2025/26 was the first year you needed a tax return, this is the point to make sure HMRC knows about it.
31
Paper Self Assessment deadline for 2025/26Self-Assessment
Most people file online, but if you file on paper the return must reach HMRC by 31 October.
December 2026
30
PAYE coding collection cut-off for online filersPAYE
If you want some tax collected through your PAYE code instead of a lump-sum payment, this is the key online filing date to remember.
January 2027Most important month of the year
31
Online Self Assessment filing deadline for 2025/26Self-Assessment
This is the main filing deadline for 2025/26. Missing it means immediate penalties.
31
Tax payment deadline for 2025/26Self-Assessment
Any balancing payment due for 2025/26 must be paid by this date. Interest starts straight away on late payment.
31
First payment on account for 2026/27Self-Assessment
If payments on account apply to you, the first 2026/27 payment falls alongside the balancing payment.
April 2027End of 2026/27 tax year
5
2026/27 ISA deadline - last chanceISA
Final day to use your 2026/27 ISA allowances. Any unused allowance is lost permanently at midnight.
5
Pension carry forward - last chance for 2023/24Pension
If carry forward matters for a larger pension contribution, this is the final point to use any remaining 2023/24 allowance.
6
2027/28 tax year beginsTax Year
A new allowance cycle begins. Reopen the current-year rates page and update hub before making fresh planning decisions.
Dates that do not move - remember these always
| Date | What happens | Miss it and... |
|---|---|---|
| 5 April | ISA allowance expires (adult ISA, JISA and LISA year-end point) | Allowance lost permanently - cannot be carried forward |
| 6 April | New tax year begins - new allowances, new thresholds and a fresh planning cycle | N/A - automatic |
| 5 October | Self-assessment registration deadline (first-time filers) | £100 minimum penalty — and you still have to file |
| 31 October | Paper self-assessment deadline | Automatic penalty — file online instead (31 January deadline) |
| 31 January | Online self-assessment filing AND payment deadline | Immediate £100 penalty; interest on unpaid tax from midnight |
| 31 July | Second payment on account | Interest charged from 1 August |
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