Missed call vs answered call: the revenue maths for trades

Let's do the arithmetic properly, using a realistic sole-trader plumber as the example. No hype — just the numbers a working tradesperson would recognise.

The setup

Meet a fictional-but-typical plumber: charges £80–£120 for routine jobs, does boilers, leaks and the odd bathroom. Works alone, on the tools most of the day.

Calls in a typical week: 15 inbound calls (existing customers + new enquiries).

Calls answered while mid-job: realistically 6–8. The rest hit voicemail during working hours; evening and weekend calls go unanswered entirely.

Calls that were genuine new work: say 5 per week.

The answer-every-call version

With a receptionist (human or AI) answering every call:

• All 5 new enquiries are captured, quoted or booked.
• At a 60% booking rate and £110 average first job: 5 × 0.6 × £110 = £330/week in captured new work.
• Annual: ~£17,000 of first-job revenue.

The voicemail version

• Most voicemail-bound callers don't leave a message — say one of the five does.
• That one caller is often already losing patience; you win maybe half of them.
• Captured: ~£30–60/week. Over a year, a gap of roughly £14,000–£15,000 versus the answer-every-call version — before counting the referrals those customers generate.

Now layer lifetime value: a captured boiler-service customer repeats annually and is first in line for the £2,500 replacement. Trades run on relationships that start with an answered phone.

The cost side

• Traditional answering service: typically £1–£2 per minute or per-call fees — realistic £150–£400/month at this call volume, message-taking only.
• Part-time receptionist: £1,000+/month, office hours only.
• AI receptionist: £29–£99/month flat, 24/7, answers and books.

The honest caveat

The maths assumes the assistant actually converts — which is why booking capability matters more than "answering". A message-taking service moves the needle less than a service that books the job there and then.

Run your own numbers: your average job value × your genuine enquiry rate × the calls you can't take. For nearly every trade business, the delta is thousands a year.