Tax-Year End Allowance Optimiser Calculator (UK)

What is the Tax-Year End Allowance Optimiser?

The Tax-Year End Allowance Optimiser helps you see which UK tax allowances you may still have available before the tax year ends on the 5th of April.

It brings together ISAs, pensions, Capital Gains Tax allowances, dividend income, savings interest, and other common tax planning areas into one place. The goal is to help you spot opportunities you may have missed before the tax year resets.

This is an illustrative planning tool, not a tax return or personalised tax advice.

How the Calculator Works?

Enter your income, pension contributions, ISA subscriptions, investment income, unrealised gains, and available cash.

The calculator estimates:

  • Which allowances you have already used
  • Which allowances may still be available
  • Potential tax savings or tax deferral opportunities
  • A prioritised list of actions to consider before the 5th of April

The results are designed to help you identify areas worth exploring further with an accountant or financial adviser.

Step 1: Enter Your Details

Add your income, pension contributions, ISA subscriptions, dividends, savings interest, and investment portfolio information.

Step 2: Review Your Allowances

See how much of your ISA, pension, dividend, savings, and capital gains allowances have been used and what may remain.

Step 3: Explore Potential Opportunities

Review the estimated tax savings, ranked action list, and areas that may be worth considering before the end of the tax year.

Disclaimer: This calculator provides illustrative estimates only and should not be used as a tax return or filing tool. UK tax rules can be complex and personal circumstances vary. Always check official guidance and consider professional advice before making significant decisions.

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Example scenarios

How different households might use the optimiser before the 5th of April

Tax-year planning is often about spotting opportunities before allowances disappear. These examples show how different households might use the calculator to identify actions worth considering before the tax year ends.

💼

Ben, avoiding the £100k tax trap

Salary: £108,000
Pension contributions: £8,000
Cash available: £15,000

Ben wants to see whether increasing pension contributions before 5 April could help restore some of his Personal Allowance and reduce his effective tax rate.

  • Reviews Personal Allowance tapering
  • Models additional pension contributions
  • Checks estimated tax relief available
👨‍👩‍👧‍👦

Helen and Mark, using family allowances

Household income: £120,000
ISA subscriptions: £14,000
Two children receiving Child Benefit

Helen and Mark want to understand whether unused ISA allowances and pension contributions could improve their overall tax position before the year ends.

  • Checks remaining ISA capacity
  • Reviews Child Benefit charge exposure
  • Explores pension contribution opportunities
📈

Oliver, sitting on large investment gains

GIA value: £280,000
Unrealised gains: £55,000
Cash available: £10,000

Oliver wants to understand whether using part of his Capital Gains Tax allowance and ISA allowance before 5 April could improve his long-term position.

  • Reviews unrealised gains
  • Explores Bed-and-ISA opportunities
  • Checks allowance usage before reset
These examples are illustrative only. The calculator uses simplified assumptions and does not replace personalised tax advice, a tax return, or professional planning.

What is the Tax-Year End Allowance Optimiser?

The Tax-Year End Allowance Optimiser is a UK planning tool that helps you review which tax allowances may still be available before 5 April. It brings together ISAs, pensions, capital gains, dividends, savings interest, and other common tax planning areas into one place.

What does the Tax-Year End Allowance Optimiser do?

It helps you review several common UK tax allowances before 5 April and highlights areas where you may still have unused capacity.

Which allowances does it cover?

The calculator looks at ISA allowances, pension allowances, Capital Gains Tax allowances, dividend income, personal savings allowances, and several other common tax planning areas.

Does this calculate my tax return?

No. The calculator is designed as a planning tool rather than a filing tool.

Does it include pension tax relief?

Yes. The calculator estimates potential pension tax relief using simplified assumptions.

Does it include Capital Gains Tax?

Yes. It includes a simplified review of capital gains allowances and unrealised gains.

Does it calculate the High Income Child Benefit Charge?

It provides an indicative flag and planning prompts, but does not perform a complete tax calculation.

Does it include Marriage Allowance?

Yes. The calculator considers Marriage Allowance eligibility under simplified assumptions.

Does it model tapered pension allowances?

No. Tapered annual allowance calculations are not fully modelled and may require professional advice.

Does it include Scottish tax bands?

No. The calculator uses simplified assumptions and does not fully model Scottish income tax rates.

Can couples use the calculator?

Yes. Married couples and civil partners can model household allowances under simplified assumptions.

What happens on the 6th of April?

Most annual allowances reset for the new tax year, which is why many people review their position before the 5th of April.

Can I export my results?

Yes. The calculator includes CSV download functionality and may optionally use email capture depending on site configuration.

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These calculators are built by a Certified Money First Aider to help you think more clearly about money and time. Money First Aid® is about practical, non-judgemental support for financial wellbeing. The calculators can certainly help you make informed decisions, but they are not regulated financial advice.

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