Tax

Tax Year End Checklist UK — Don't Miss Out

Use it or lose it before 5 April. ISA allowance, pension contributions, Capital Gains allowance, Marriage Allowance, and more. Complete tax year end checklist.

By PocketWise · · 4 min read

Tax information is based on HMRC rules for the 2026/27 tax year. Tax rules can change — always verify current rates at GOV.UK. This is not tax advice. Consider consulting a qualified tax adviser for your personal situation.

Don’t let valuable allowances expire unused. Here’s what to check before 5 April.

Key Dates

Important Deadlines

Date Event
5 April Tax year ends
6 April New tax year begins
Allowances reset ISA, CGT, dividend, pension annual
Can’t carry forward Most allowances lost

Planning Timeline

When Action
February Review and plan
March Take action
Early April Final checks
5 April Deadline

ISA Allowance (£20,000)

The Basics

Feature Details
Annual allowance £20,000
Carry forward No — use it or lose it
Split between Cash ISA, Stocks & Shares ISA, LISA
Tax benefit All growth/interest tax-free

ISA Types

Type 2025-26 Allowance
Cash ISA Part of £20,000
Stocks & Shares ISA Part of £20,000
Lifetime ISA £4,000 max (within £20,000)
Innovative Finance Part of £20,000
Total across all £20,000

Action Required

Situation Action
Haven’t used any Open ISA, deposit what you can
Partially used Top up
Don’t have £20k Put in what you can
Already maxed You’re done

Quick Wins

If You Have Do
£100+ spare Open Cash ISA
Regular savings Use Regular Saver ISA
Investments outside ISA Bed and ISA (see below)
Savings goals Lifetime ISA (if under 40)

Pension Contributions

Annual Allowance

Limit Details
Standard £60,000 per year
Earnings cap Can’t exceed earnings
Carry forward Up to 3 years unused allowance
High earners May be tapered

Tax Relief

Tax Rate On £1,000 Contribution
Basic (20%) Costs you £800, worth £1,000
Higher (40%) Costs you £600, worth £1,000
Additional (45%) Costs you £550, worth £1,000

Action Required

Situation Action
Employer scheme Check if can increase contribution
Self-employed Personal pension contribution
High earner Use carry forward if available
Under-contributed Consider lump sum

Carry Forward

How It Works Details
Unused allowance From last 3 years
Must have earned In each year
Use current year first Then oldest unused
Check records What did you contribute?

Capital Gains Tax

Annual Exempt Amount

Year Tax-Free Gains
2025-26 £3,000
Unused Cannot carry forward
Above this Taxed at 18%/24%

Bed and ISA

Step Action
1 Sell investments with gains (up to £3,000 profit)
2 Gains are tax-free
3 Repurchase same investments in ISA
4 Future growth is tax-free
Watch Out Details
Trading costs May eat into benefit
30-day rule Doesn’t apply to bed and ISA
Same-day rebuy In ISA is fine
Only if gains No point if losses

Capital Losses

| Can | Offset against gains | | Carry forward | Unlimited years | | Report | On Self Assessment | | Strategy | Realise losses before year end |

Marriage Allowance

What It Is

Feature Details
Transfer £1,260 of Personal Allowance
From Non-taxpayer to basic rate spouse
Worth £252 per year
Backdate Up to 4 years

Eligibility

Person Requirement
Lower earner Income under £12,570
Higher earner Basic rate taxpayer (under £50,270)
Relationship Married or civil partners

Action Required

Step Action
Check eligibility Both conditions met?
Apply gov.uk/marriage-allowance
Claim backdate Get up to £1,000+ lump sum
Take 5 minutes Worth doing

Dividend Allowance

Tax-Free Dividends

Year Allowance
2025-26 £500
Above this Taxed (8.75%/33.75%/39.35%)

Action Required

Situation Action
Dividends in ISA Already tax-free
Dividends outside ISA Consider Bed and ISA
Company director Time dividend payments

Gift Aid Donations

How It Works

Feature Details
Charity claims 25p for every £1 you give
Higher rate taxpayers Can claim extra 25p back
Must donate In the tax year

Year End Action

If You Action
Plan to donate Do it before 5 April
Higher rate taxpayer Include in Self Assessment
Made donations Keep records

Other Allowances

Personal Allowance

| Amount | £12,570 tax-free income | | Action | Ensure salary sacrifice doesn’t waste it | | Couples | Can both use own allowance |

Savings Allowance

| Basic rate | £1,000 interest tax-free | | Higher rate | £500 interest tax-free | | Additional rate | £0 interest tax-free |

| Action | Check if exceeding — use ISAs |

Trading Allowance

| Amount | £1,000 | | For | Self-employed/side income | | If under | Don’t need to report | | If over | Only profit above £1,000 taxed |

Summary: Tax Year End Checklist

Must-Do Before 5 April

Action Done
Use ISA allowance (any amount) ☐
Review pension contributions ☐
Check Marriage Allowance ☐
Realise gains/losses if needed ☐
Make Gift Aid donations ☐

Check Eligibility

Allowance Eligible Using
ISA (£20,000) ☐ ☐
Lifetime ISA (£4,000) ☐ ☐
Pension (£60,000) ☐ ☐
Marriage Allowance ☐ ☐
CGT allowance (£3,000) ☐ ☐

By Amount to Save

Action Potential Tax Saving
Marriage Allowance £252/year
Full ISA (over time) Hundreds long-term
Pension contribution 20-45% of contribution
CGT allowance Up to £720
Higher rate Gift Aid 25p per £1 donated

December/January

Action Done
Review last year’s actions ☐
Check for carry forward (pension) ☐
Plan contributions ☐

February/March

Action Done
Make pension contributions ☐
Top up ISA ☐
Bed and ISA if applicable ☐
Marriage Allowance claim ☐

Key Contacts

Resource For
Gov.uk All applications
HMRC Tax queries
Pension provider Contribution deadlines
ISA provider Transfer times

Don’t leave money on the table. Most of these take minutes to action but can save hundreds of pounds. Even if you can only do one thing, use some of your ISA allowance — future you will appreciate the tax-free growth.

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Sources

  1. HMRC — Tax year dates and deadlines