Most small businesses judge a website on traffic. That number means nothing until you connect it to two others: how many visitors send an enquiry, and how many enquiries become paying clients. Put the three together and you get the only figure that matters for a service business — how many visitors, and how much spend, it takes to win one client. This page gives you the formulas, a set of worked scenarios and the levers that move each number.
The three formulas
You need three inputs, all of which you can pull from your own records: your enquiry conversion rate (enquiries ÷ website sessions), your close rate (new clients ÷ enquiries) and the value of a client (first-year gross profit, not revenue). Everything else follows.
- Visitors per client = 1 ÷ (enquiry conversion rate × close rate)
- Cost per client (paid traffic) = visitors per client × average cost per click
- Break-even cost per click = client value ÷ visitors per client
Use gross profit for client value. A £6,000 project that costs you £3,500 to deliver is worth £2,500 to this calculation — using revenue will tell you a campaign is profitable when it is not.
Worked scenarios
The table below runs the formulas across five combinations of conversion and close rate, with a £3 cost per click and a client worth £2,500 in first-year gross profit. These are illustrative inputs, not industry benchmarks — replace them with your own numbers, because your market, pricing and sales process will differ.
| Enquiry conversion | Close rate | Visitors per client | Cost per client at £3 CPC | Break-even CPC |
|---|---|---|---|---|
| 1% | 10% | 1,000 | £3,000 | £2.50 |
| 1% | 20% | 500 | £1,500 | £5.00 |
| 2% | 20% | 250 | £750 | £10.00 |
| 2% | 30% | 167 | £500 | £15.00 |
| 3% | 30% | 111 | £333 | £22.50 |
Read the table from top to bottom: moving enquiry conversion from 1% to 2% halves the traffic you need, and the same is true of moving close rate from 10% to 20%. Improving both multiplies. That is why fixing the website and the sales follow-up usually beats buying more traffic.
Where to find your real numbers
You do not need an analytics platform to start. Count enquiries from your inbox and phone log for the last 90 days, count the clients those enquiries became, and take sessions from whatever analytics or hosting statistics you have. If you run Google Ads, the platform reports your actual average cost per click.
- Enquiries: form submissions, calls and direct emails that mention the website — count them for one full quarter.
- Close rate: clients won ÷ enquiries received in the same period. Exclude spam and job applicants.
- Client value: average first-year gross profit per client, from your accounts rather than a quote.
- Cost per click: from Google Ads, or leave paid traffic out and use the visitors-per-client figure alone.
The levers that move each number
Each input has a small number of practical levers. Most of them are on the website or in the first hour after an enquiry arrives.
| Input | Main levers | Who owns it |
|---|---|---|
| Enquiry conversion | Form length, mobile load speed, clear pricing signals, visible proof (reviews, case studies), a phone number that works on tap | Website |
| Close rate | Speed of first response, a written quote within a day, qualifying questions on the form, follow-up after the quote | Sales process |
| Client value | Packaging, retainers and maintenance plans, repeat work | Business model |
| Cost per click | Search terms bought, match types, negative keywords, landing-page relevance | Paid search |
A worked example
A London accountancy practice gets 1,200 website sessions a month and 12 enquiries — a 1% conversion rate — and wins 2 of those 12 as clients, a close rate of about 17%. At those rates it needs roughly 600 visitors per client.
Two changes — cutting the contact form from nine fields to four, and replying to every enquiry within the hour — lift conversion to 1.5% and close rate to 25%. Visitors per client falls to about 267. The same 1,200 monthly sessions now produce four to five clients instead of two, with no extra traffic bought.
Traffic is an input. The number that pays the bills is visitors per client.
What this means for you
Copy the three formulas into a spreadsheet, fill in a quarter of your own data and you will know which lever is worth pulling first. If the answer is the website, that is the work we do — and we quote it at a fixed price before anything starts.
Related service: Website Development