FinToolSuite

Will Planning Calculator

Updated April 17, 2026 · Planning · Educational use only ·

What a will really costs.

Calculate will planning cost - solicitor vs DIY comparison. Enter solicitor will cost and diy will cost for an instant result.

What this tool does

This tool compares solicitor vs DIY will costs. Enter base costs, complexity factor, and years of validity.


Enter Values

Formula Used
Solicitor cost
Complexity factor

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Disclaimer

Results are estimates for educational purposes only. They do not constitute financial advice. Consult a qualified professional before making financial decisions.

Making a will costs 150-500 for basic solicitor service, 30-90 for DIY online services. For simple estates, DIY is usually fine. Complex estates (business ownership, trusts, multiple properties) benefit from solicitor guidance despite higher cost.

400 solicitor will lasting 10 years amortises to 40/year. DIY 60 lasting 10 years = 6/year. The 340 upfront gap represents peace of mind and reduced error risk. This calculator shows both sides.

Review wills every 5-7 years or after major life events (marriage, divorce, birth, significant inheritance). Letting a will become outdated causes more problems than any saving from the DIY route.

A worked example

Try the defaults: solicitor will cost of 400, diy will cost of 60, complexity factor of 1, years will is valid of 10. The tool returns 400.00. You can adjust any input and the result updates as you type — no submit button, no reload. That's the real power here: seeing how sensitive the output is to one or two assumptions.

What moves the number most

The result responds to Solicitor Will Cost, DIY Will Cost, Complexity Factor, and Years Will Is Valid. Not every input has equal weight. Flip one at a time toward extreme values to feel which ones move the needle most for your situation.

The formula behind this

Solicitor lifetime = cost × complexity. Annualised = lifetime / years. Difference vs DIY shown. Everything the calculator does is shown in the formula box below, so you can check the math against your own spreadsheet if you want.

The annual review habit

Plug new numbers in every year. Income changes, expenses shift, markets move. A plan that isn't revisited quietly drifts out of date. This tool is cheap to re-run — so re-run it.

What this doesn't capture

Real plans get re-run against new information every year or two. The result here is a reasonable direction, not a destination. Treat it as a starting point for thinking, not a commitment to a specific future.

Example Scenario

Solicitor £400 £ × 1x vs DIY £60 £ = $400.00.

Inputs

Solicitor Will Cost:400 £
DIY Will Cost:60 £
Complexity Factor:1
Years Will Is Valid:10 years
Expected Result$400.00

This example uses typical values for illustration. Adjust the inputs above to match a specific situation and see how the result changes.

Sources & Methodology

Methodology

Solicitor lifetime = cost × complexity. Annualised = lifetime / years. Difference vs DIY shown.

Frequently Asked Questions

When does DIY not work?
Businesses to pass, multiple properties, trusts for minor children, complex family arrangements (step-children, unmarried partners), significant assets overseas. Any of these makes solicitor advice worthwhile.

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