UK Tax Year Dates, Changes and Deadlines 2026/27 — What's New and When Tax Year End Guide UK — What to Do Before April 5th Essential actions to take before the UK tax year ends on April 5th. ISA deadlines, pension contributions, CGT allowance, and more ways to save tax.
By James Whitfield
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23 March 2026
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Last reviewed: 14 August 2026
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4 min read Don’t let valuable tax allowances expire. Here’s your checklist for actions before April 5th.
Key Deadlines Summary Use It or Lose It Allowances Allowance Amount Deadline ISA £20,000 April 5th LISA £4,000 (within ISA) April 5th Junior ISA £9,000 April 5th Pension annual allowance £60,000 April 5th Capital Gains Tax allowance £3,000 April 5th Dividend allowance £500 April 5th Annual gift exemption £3,000 April 5th
ISA Allowance Why It Matters What You Get Benefit £20,000 annual limit Tax-free Interest No tax ever Dividends No tax ever Capital gains No tax ever
Types of ISA ISA Type Limit Best For Cash ISA £20,000 total Short-term savings Stocks & Shares ISA £20,000 total Long-term growth Innovative Finance ISA £20,000 total P2P lending LISA £4,000 (part of £20k) First home/retirement
Action Checklist Task Priority Check current ISA balance High Top up if under £20,000 High Open ISA if don’t have one High Consider which type for needs Medium
Last-Minute ISA Tips Tip Why Open account first Even with £1 Can add more later Before deadline One of each type Per tax year Transfer old ISAs anytime Doesn’t use allowance
Pension Contributions Annual Allowance Allowance Amount Standard £60,000 Or 100% of earnings Whichever lower Carry forward 3 years if unused
Tax Relief Tax Band Relief on £1,000 Basic rate (20%) £250 Higher rate (40%) £500 Additional rate (45%) £563
Carry Forward Rules Year Unused Can Use 2022/23 Yes 2023/24 Yes 2024/25 Yes 2021/22 Expired
Action Checklist Task Priority Check pension contributions YTD High Calculate remaining allowance High Check carry forward available High Make additional contribution High if affordable
Salary Sacrifice If You Can Do This Arrange by early March Give payroll time One-off bonus sacrifice Before year end NI saving too Salary sacrifice bonus
Capital Gains Tax Annual Exemption Detail Amount 2026/27 exemption £3,000 Gains above exempt Taxed
Bed and ISA Strategy How Sell investments Crystallise gain Rebuy in ISA Same day Use CGT allowance £3,000 tax-free Future growth Tax-free in ISA
Bed and Spouse Strategy How Sell investments Crystallise gain Spouse rebuys Different person Both use allowance £6,000 combined
Losses Action Benefit Crystallise losses Before April 5th Offset against gains Reduce tax Carry forward Unlimited
Dividend Allowance Current Allowance Tax Year Dividend Allowance 2026/27 £500
Action If You Have Dividends Consider Over £500 Move to ISA before year end In private company Timing of dividends Portfolio Rebalance into ISA
Marriage Allowance What It Is Transfer Amount From non-taxpayer £1,260 of allowance To basic rate spouse Saves £252/year
Backdating Can Claim Value 4 tax years back Up to ~£1,000
Action Check Do One spouse non-taxpayer? Claim Not yet claimed? Backdate Before April 5th For this year
Gift Exemptions Annual Exemptions Exemption Amount Annual gift £3,000 Small gifts £250 per person Wedding (parents) £5,000 Wedding (grandparents) £2,500
Inheritance Tax Planning Action Benefit Use £3,000 exemption Reduces estate Carry forward 1 year £6,000 if unused last year Regular gifts from income Exempt if pattern
Employer Benefits Use Before Year End Benefit Action Childcare vouchers Order by March Eye care vouchers Use allowance Employee discounts Before expiry Annual wellness budget If provided
Salary Sacrifice Options Option Deadline One-off pension boost Early March Reduce taxable income Before year end
Income Management For High Earners If Income £100k-£125k Consider Pension contribution Restore Personal Allowance Timing of bonuses Manage tax band Gift Aid Reduce adjusted income
Child Benefit Clawback If Earning £50k-£60k Action Pension contribution Reduces income May keep Child Benefit Below £50k threshold
Self-Assessment Key Dates Date Action By April 5th Use allowances By October 31st Paper return deadline By January 31st Online return + payment
Check Before Year End Task Priority Estimate tax bill Plan payment Payments on account Correct? Claim all reliefs Before filing
Month-by-Month Checklist February Task Status Review ISA contributions □ Check pension YTD □ Plan CGT usage □
March Task Status Top up ISA □ Additional pension if affordable □ Bed and ISA transactions □ Use gift exemptions □
Early April (Before 5th) Task Status Final ISA top-up □ Last pension contributions □ Complete CGT planning □ Check all allowances used □
Quick Wins Summary Action Tax Saving (Higher Rate) Use £20k ISA Future gains tax-free Extra £10k pension £4,000 back Use £3k CGT Saves £540 Marriage allowance £252 Gift £3k IHT saving (40% eventually)
Common Mistakes Mistake Avoid By Leaving ISA until April 4th Plan in February Forgetting carry forward Check 3-year history Missing deadlines Set calendar reminders Not opening accounts Open early, contribute later
Summary Deadline Allowance Amount April 5th ISA £20,000 April 5th Pension £60,000 April 5th CGT £3,000 April 5th Dividends £500 April 5th Gifts £3,000 January 31st Self-Assessment N/A
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