Tool
Lead response cost calculator
Work out what late and missed out-of-hours enquiries cost your business each month and each year, using your own numbers.
VAULT 33|27 · Updated 12 November 2026 · 1 min read
How it works
Five inputs from your own business: enquiries per month (A), the share arriving outside office hours (B), your enquiry-to-client rate (C), the value of a client (D), and your honest estimate of how many out-of-hours enquiries are lost because the reply comes too late (E).
Value at risk = A × B × E × C × D
Calculator
What slow replies cost you
Your own numbers, nothing stored. The formula is A × B × E × C × D, explained above.
All channels: calls, forms, messages
Evenings, nights and weekends
Your normal conversion rate
Revenue from one new client
Your honest estimate. If unsure, start cautious, around 10 to 15%
Enquiries lost a month
6.3
Value at risk a month
£1,134
A year
£13,608
An estimate built on your inputs, not a promise. The most uncertain number is E: measure it for a month to replace the guess with your own data.
How to make the estimate stronger
The weakest input is E. For one month, log when each enquiry arrives and when it gets its first real reply, then check which late replies never turned into clients. Our lead response time guide explains the research behind this, including what it does not prove.
Open your vault.
A free systems audit of your business: where enquiries leak and exactly what we would build.
Book your free audit