Ask most service business owners how many calls they missed last month and you get a shrug and a guess. That's not carelessness. There's no place the number lives. Your phone shows recent calls for a while and then it doesn't, voicemail only counts the people who bothered to leave one, and nobody is writing down the ones that rang out while you were under a sink.
The guess is almost always low. Here's how to replace it with something real.
Three numbers you already have
Your average job value. Not your biggest job — your average. Add up last month's invoices and divide by the number of jobs. Most owners overestimate this because the memorable jobs are the big ones.
Your close rate on calls that reach you. Of the people who actually get you on the phone, how many book something? For most trades this lands somewhere between a third and two thirds. If you've never measured it, start counting this week.
Your missed calls. This is the one you don't have. Your phone carrier does, though. Most carriers show call history in the account portal, including calls that went unanswered. Pull last month.
Multiply the three together and you have a floor for what unanswered calls cost you last month. A floor, not a ceiling — because it assumes the caller was worth one average job and nothing more.
Why it's a floor
The arithmetic above misses two things that matter more than the first job.
The first is repeat work. A customer who calls once and gets an answer often calls again, for years. When you lose the first call you don't lose one job, you lose the whole relationship, and you never find out it existed.
The second is that the caller doesn't stop calling. They call the next name on the list. That business now has the customer you would have had, and the referrals that customer makes go there too.
The part people get wrong about voicemail
There's a common assumption that a missed call isn't really lost, because serious people leave a message. That was true when the alternative was driving somewhere. It isn't true now.
When someone needs a service business, they are usually holding a phone with a search results page still open. Hanging up and tapping the next number costs them four seconds. Leaving a voicemail costs them thirty seconds and an unknown wait. Most people take the four seconds, and the ones who don't are disproportionately the ones with a problem so bad they'll wait — which is not the same as the ones with the best jobs.
So the voicemail count is not the missed call count. It's a fraction of it, and you can't tell what fraction from the voicemails alone.
What to do about it, ranked by effort
Measure it. Even if you change nothing else, knowing the number changes how you think about the rest of this list. Pull the carrier data monthly.
Set expectations in the voicemail greeting. "I'll call you back within two hours" converts better than a beep, because it gives the caller a reason to spend the thirty seconds. Only do this if it's true.
Return calls in a block, early. A callback at 7am the next morning reaches far fewer people than one at 4pm the same day. Urgency decays fast.
Have the phone answered. By a person, an answering service, or a system — the caller mostly cares that something picks up, takes their details, and tells them what happens next. What they won't do is wait around to find out whether you got the message.
The point isn't that any one of these is the answer. It's that "we miss some calls" is a sentence, and the thing you can actually act on is a number.