FinToolSuite

Prenuptial Agreement Cost Calculator

Updated April 17, 2026 · Modern Life Events · Educational use only ·

Estimated legal and advisory cost of a prenup.

Estimate the total cost of drafting a prenuptial agreement including legal fees for both parties and financial disclosure.

What this tool does

Enter expected hours per lawyer, hourly rates, and disclosure cost. The tool shows total estimated cost of preparing the agreement.


Enter Values

Value is unusually high — please double-check

Value is unusually high — please double-check

Formula Used
Legal hours
Hourly rate
Disclosure and valuation costs

Spotted something off?

Calculations, display, or translation — let us know.

Disclaimer

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

Drafting a prenup usually involves two lawyers — one for each party — plus financial disclosure. Typical billing: 8-15 hours per side at 250-500/hour, plus 500-2,000 for disclosure and schedules. That puts typical total cost in the 4,000-15,000 range. Complexity drives cost: more assets, cross-border issues, or prior marriages all push it up.

Legal-cost estimator.

A worked example

Try the defaults: party a legal hours of 10, party a hourly rate of 350, party b legal hours of 10, party b hourly rate of 350. The tool returns 8,000.00. 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 Party A Legal Hours, Party A Hourly Rate, Party B Legal Hours, Party B Hourly Rate, and Disclosure & Valuation. Frequency and unit price pull the total in different directions. The biggest surprise for most people is how small recurring amounts compound into large annual figures — that's where this calculation earns its keep.

The formula behind this

Hours × rate for each party's representation plus any disclosure costs. Assumes independent legal advice on both sides — which is the standard requirement for the agreement to hold up. Everything the calculator does is shown in the formula box below, so you can check the math against your own spreadsheet if you want.

What the number doesn't include

Life events generate side costs: time off work, travel for guests, aftercare, lost weekends. The figure here covers the direct costs. Noting the indirect ones alongside avoids the post-event surprise.

What this doesn't capture

Life events generate side costs the figure doesn't include: time off work, lost income, travel for others, aftercare. Add 10–15% to the direct number as a buffer; the items you haven't thought of usually fill most of it.

Example Scenario

Prenup cost produces a total estimate based on the inputs provided.

Inputs

Party A Legal Hours:10
Party A Hourly Rate:350 £
Party B Legal Hours:10
Party B Hourly Rate:350 £
Disclosure & Valuation:1,000 £
Expected Result£8,000.00

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

Hours × rate for each party's representation plus any disclosure costs. Assumes independent legal advice on both sides — which is the standard requirement for the agreement to hold up.

Frequently Asked Questions

Do both parties need separate lawyers?
Typically yes. Independent legal advice for both parties is a core requirement for enforceability in most jurisdictions. Shared representation undermines the agreement.
Can we DIY with a template?
Possible but risky. Template prenups are routinely set aside by courts for procedural defects. The whole point of a prenup is enforceability — half-done is worse than none.
Does complexity really push cost that much?
Yes. Cross-border assets, trusts, business interests and blended families each add hours. Full disclosure can take weeks.
Any ongoing cost after signing?
Usually none, unless you amend the agreement (a postnup) or a material change in circumstances warrants revisiting.

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