How to estimate the cost of missed enquiries
A worked missed-call calculation, how to count your own enquiries and how to decide whether a change is worth making.
Missed enquiries matter when they represent opportunities your business could realistically serve. This article works through phone enquiries at a plumbing company. Its job values and conversion assumptions are examples; your calculation should use your own data.
About a quarter of a job, each. Here's the sum: missed calls a week × 4 weeks, treat one in four as a job you'd have won, × your average job value, then cap the result at 25% of annual revenue so it stays honest. Say you miss five calls a week at $450 a job. That's 20 missed calls a month, five jobs, $2,250 a month, $27,000 a year.
The quarter rule
I call it the quarter rule because a quarter shows up twice. One in four missed calls counts as a lost job. And if you tell the calculator your revenue, I hold the displayed total at a quarter of it as a sanity check, and show you the uncapped sum beside it.
Both quarters are there to keep the number believable, not to make it big.
One in four is low on purpose, and it's a default you can change in the calculator, not a floor I'm claiming for your business. Some of the calls you miss are salesmen, wrong numbers, and the customer from last week asking where the invoice is. Some are quotes for a bathroom refit that would have gone to three other plumbers anyway. So I don't count them all. I count one in four, and I'd argue that's the floor for emergency work, not the ceiling. When someone rings at ten at night with water coming through the kitchen ceiling, the job is won by whoever picks up. There's no shortlist.
The cap exists because an early version of my calculator once produced a loss bigger than the tester's annual revenue. Nobody believes a number like that, and they shouldn't. In the businesses I've looked at, no phone leak has come close to a quarter of revenue, so I treat anything past that as a reason to check the inputs, not as a result. It's my judgment call, said out loud, not a law of economics. If your sum comes out higher, count your missed calls for a week before you trust either number.
Run it at the calculator. The arithmetic is printed next to the result so you can argue with each step.
A worked example in dollars
Say you run a two-van plumbing outfit and you miss five calls a week. Not calls that went to voicemail and got returned in ten minutes. Calls you never got back to, or got back to after the customer had found someone else.
Five a week × 4 weeks is 20 missed calls a month. One in four is five jobs you'd have won. Five jobs × $450 is $2,250 a month. Over your year, $2,250 × 12 is $27,000.
Where does $450 come from? HomeAdvisor's plumber cost guide, updated June 2026, puts a plumber visit at $182 to $501 with an average of $341, and says emergency calls outside regular hours cost an extra $100 to $300. A mix of daytime jobs and a few emergencies lands around $450. If yours is $300, use $300.
Add your revenue and the cap does its job. Say the business turns over $400,000: a quarter of that is $100,000, so $27,000 stands.
The same sum in pounds
Say you're a one-van plumber in the UK and you miss four calls a week, mostly evenings and Saturdays. Call the average job £250. MyJobQuote's emergency plumber guide, updated August 2026, has the call-out fee at around £75 plus about £60 an hour, and puts a typical emergency repair at £135 to £255 before parts. So £250 is an emergency call-out, a couple of hours and a part. That's what most of those evening calls are.
Four a week × 4 weeks is 16 missed calls a month. One in four is four jobs you'd have won. Four × £250 is £1,000 a month, and over your year that's £12,000.
Now the cap. If you turn over £40,000 a year, a quarter is £10,000. The calculator shows £10,000, not £12,000, and tells you it capped it. That's not me being generous. It's me refusing to hand you a number you'd be right to dismiss.
After-hours and emergency calls are the ones that leave
Not every missed call is lost. The customer who wants a quote on a new bathroom will leave a message, or ring back tomorrow, or fill in the form on your website. She's comparing three plumbers anyway. Missing her call costs you a little.
The call at nine on a Saturday night is different. That's a burst pipe, a cylinder dripping through the ceiling, a toilet backing up in a house with one toilet. Nobody leaves a voicemail with water on the floor. They hang up before the greeting ends and ring the next name on Google. Whoever answers gets the job, gets to charge the emergency rate, and gets the customer. She's not comparing anyone. She's done.
So the after-hours calls fail on both counts. They leave more often, because the caller can't wait. And they're worth more, because emergency work carries a premium: HomeAdvisor has US plumbers charging time and a half to triple their hourly rate outside regular hours, and MyJobQuote has London emergency call-outs at £90 to £120 before the first hour of work.
And the loss doesn't stop at one job. The customer who got someone else on Saturday night now has a plumber. That firm gets her next boiler service, and the neighbour she'd have sent to you.
Count your own missed calls for one week
My five-a-week is a placeholder. Yours is a fact, and you can have it in seven days.
Pick a normal week, Monday to Sunday. Include the weekend. The weekend is the point.
Then use whichever of these you've got:
- Your phone's call log. On an iPhone, Recents shows missed calls in red. On Android, the call history has a Missed filter. If the business line rings on your mobile, this is your truth.
- Your carrier's online account. Most business lines, mobile or landline, have an itemised log of incoming calls online. It catches the ones that never made your handset ring because you were in a basement with no signal.
- A tally sheet. Masking tape on the dashboard, a pen in the door pocket. One stroke every time you hear it ring and can't get to it. Low tech, and it catches the calls you felt in your chest pocket but never looked at.
At the end of the week, sort the count into three piles. Missed during working hours. Missed after hours and at weekends. And missed but called back within half an hour. That third pile isn't lost. Take it out.
What's left is your number. Put it into the calculator with your real average job value and you've got something better than any statistic I could quote you. Most of the numbers you'll read about missed calls trace back to one study: 411 Locals tracked 85 businesses across 58 industries for 30 days in 2016 and found only 37.8% of calls answered by a person, with 37.8% going to voicemail and 24.3% getting no response at all. It's a small study, it's ten years old, and it was run by a marketing company. Your tape on the dashboard is worth more.
What to do about it, in this order
Cheapest first. Most plumbers should stop at step one or two.
1. Answer more of them yourself. Check the phone at the end of every job, before you start the van. Ring back every missed call within ten minutes if you can, and always before the end of the day. A fast callback turns most daytime misses back into jobs. This costs nothing and fixes more than any tool.
2. Forward smarter. Most carriers let you ring two phones at once, or forward on no answer after a set number of rings. Put your apprentice, your partner in the business, or whoever's on call that evening as the second ring. Set a schedule so calls after five go to the on-call phone, not your pocket. Change the voicemail greeting to say when you'll ring back. An hour of setup, maybe a small monthly charge.
3. A human answering service. Real people, round the clock, reading your script and taking a message or patching the call through. Ruby starts at $250 a month for 50 receptionist minutes. AnswerConnect's entry plan is $350 a month for 200 minutes, then $2.50 a minute over. Smith.ai starts at $300 a month for 30 calls, then $11.50 a call. Good when you want a person on the line. Weak when the receptionist can't tell a dripping tap from a burst main, and when a cold snap fills one night with twenty calls and eats your minutes.
4. An AI receptionist. Here's the honest version of what mine does. It answers on the first ring. It finds out what the job is, where it is, and how urgent. Then it texts you and gets out of the way. It does not book. It does not promise a time. It does not dispatch. You ring back in a few minutes and close it yourself, from your head, the way you always have. It doesn't run out of minutes on the night it snows, and it doesn't need to know plumbing to ask the three questions that matter. It's not for everyone: in Housecall Pro's October 2025 survey of 1,040 US homeowners, 53% said they're comfortable with AI handling initial inquiries. A majority, not all. Compare its monthly price with the quote you got at step three and with the number the calculator gave you. Mine goes live for its first plumbing client in October 2026, and I'll write up what happens. How I've set it up is on the plumbers page.
When to buy nothing
I recommend against buying anything more often than you'd expect.
If your phone rings twice a day and you answer both, keep your money. If your week's tally came to two or three missed calls and you rang them all back inside the hour, you don't have a phone problem. You have a busy week. If you're booked three weeks out and don't want more work, a missed call is a filter, not a leak.
Buy something when three things are true at once. Your week's count is five or more. Most of them fall after five o'clock or at the weekend. And the yearly figure from the calculator is many times what the fix costs. If you want a second pair of eyes on those three, book a growth call. It's thirty minutes, it's free, and I'll tell you if the answer is to do nothing.
Questions people ask
What percentage of calls do small businesses miss?
The number everyone quotes is 62%, and it traces back to one study. 411 Locals tracked 85 businesses in 58 industries for 30 days in 2016 and found only 37.8% of calls answered by a person, with 37.8% going to voicemail and 24.3% getting no response. It is small, it is old, and it was run by a marketing company. Count your own for a week instead.
How much is a plumbing call-out worth?
HomeAdvisor's June 2026 guide puts a US plumber visit at $182 to $501, average $341, with service call fees of $100 to $250 and an extra $100 to $300 for emergency calls outside regular hours. In the UK, MyJobQuote's August 2026 guide has an emergency call-out fee of around £75 plus about £60 an hour, and a typical emergency repair at £135 to £255 before parts.
Is an answering service worth it for a one-van plumber?
Only if you miss calls you cannot get back to. Ruby starts at $250 a month for 50 receptionist minutes, so at HomeAdvisor's average US job of $341 it needs to catch one job a month to pay for itself. If your week's count is two or three misses and you ring them all back inside the hour, it is not worth it. If it is five or more, mostly after hours, it probably is.
Does an AI receptionist replace my office manager?
No. Mine answers the call, finds out what the job is, where it is and how urgent, then texts you and gets out of the way. It does not book, dispatch, invoice, chase quotes or order parts. It replaces voicemail, not the person who runs your office. If you already have someone answering every call, you don't need it.
How many missed calls turn into lost jobs?
Nobody has a clean figure for plumbing, so I use a deliberately low default: one in four, and the calculator lets you change it. Daytime quote calls convert lower because the customer is comparing plumbers. After-hours emergency calls convert higher because the customer hires whoever answers. If most of your missed calls come after five, the real share is above a quarter and the calculator's number is conservative.
Sources
- 1.411 Locals: Small business owners don't answer 62% of phone calls · 85 businesses, 58 industries, 30 days, January 2016: 37.8% answered live, 37.8% voicemail, 24.3% no response
- 2.Housecall Pro: Home service customer service report 2025 · 1,040 US homeowners surveyed 23 October 2025; 53% comfortable with AI handling initial inquiries
- 3.HomeAdvisor: How much does it cost to hire a plumber? · Updated June 2026: $182 to $501, average $341; service call $100 to $250; emergency calls an extra $100 to $300, time and a half to triple the hourly rate
- 4.MyJobQuote: Emergency plumber cost guide · Updated August 2026: call-out fee around £75 plus about £60 an hour; typical emergency repair £135 to £255; London call-outs £90 to £120
- 5.Ruby: Virtual receptionist pricing · Starter $250 a month for 50 receptionist minutes; Professional $395 for 100; Business $720 for 200
- 6.AnswerConnect: Your guide to plans and pricing (PDF) · Entry plan 200 minutes for $350 a month plus $49.99 setup, $2.50 per additional minute; real people 24/7
- 7.Smith.ai: Virtual receptionist pricing · Starter $300 a month for 30 calls, $11.50 per call over
Written by Ivar André Knutsen
I build and run AI systems, internal tools and workflow automation. You work directly with me from the first conversation through implementation and support. About Ivar
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