The short answer
You already have almost everything you need. Your mobile's call log, the history on your internet box/router or your phone system, and your voicemail keep a record of the calls nobody took. All that is missing is a habit: noting them down every evening for a week, in the same place, sorting them into three categories. This tally requires no software, and it answers the question that comes before all the others: how many calls are slipping through your fingers, and when.
This guide stops at counting. To turn that number into money, the guide to the cost of a missed call gives the calculation method.
Where to find your missed calls, device by device
On a mobile
The call log in the Phone app is the most direct source. It has a missed calls filter, with the time and number of each call. Three limitations to be aware of:
- It doesn't keep everything. The log holds a limited number of entries and eventually deletes the oldest ones. Check it every evening, not at the end of the week.
- It sometimes groups calls together. Several attempts from the same number may appear on a single line. Count each attempt, then note separately the number of different people.
- It only sees calls that actually reached the phone. If the mobile is switched off, has no signal, or the line is busy without call waiting, the call may go straight to voicemail without leaving a trace in the log. In that case, count the voicemail messages, and the notification texts some operators send when a number has tried to reach you.
On your operator's bill or itemised statement
The itemised statement in your online account mainly lists billed calls, in other words the calls you made. Incoming calls are often not shown. It is still useful for two things: finding the callbacks you made after a missed call, and spotting forwarded calls if you already forward to a colleague, since the operator counts them as outgoing calls. If your plan also provides a history of incoming calls, check your online account: it is then a very good source, because it doesn't depend on your phone.
On an internet box/router or a landline
Most internet boxes keep a log of calls on the landline, which, depending on the model, you can view in the box's interface or in the operator's app. The cordless handset also shows its own list, but it is short and specific to each handset: if you have several, use the box's log instead. Menus vary from one model to another; check in your online account where your line's call history is.
On a phone system
A cloud phone system or an IP PBX records every call, including those nobody took. Look for three figures in its log or statistics: unanswered calls, calls abandoned in the queue (the caller hung up before an extension became free) and calls that reached the closed message. These are three forms of missed call. If the phone system allows an export, one week's export is enough to fill in the grid below.
On voicemail
Count the messages, but don't stop there: many callers hang up without leaving one. The number of messages is a minimum, never the total.
A one-week grid to copy
Choose an ordinary week: no closure, no holidays, no exceptional event. Each evening, five minutes is enough. Copy this table onto a sheet of paper or into a spreadsheet.
| Day | Missed calls | Opening hours, line free | Out of hours | During another call | Different callers | Message left | Called back by you |
|---|---|---|---|---|---|---|---|
| Monday | |||||||
| Tuesday | |||||||
| Wednesday | |||||||
| Thursday | |||||||
| Friday | |||||||
| Saturday | |||||||
| Sunday | |||||||
| Total |
In the first column of figures, note every attempt. The next three columns break them down: added together, they should match the day's total. The last three show who kept trying, who left a trace and who you were able to reach afterwards.
Sorting each call into three categories
Opening hours, line free
You were open, the line was free, nobody picked up: you were with a customer, on site, driving, or the phone was in another room. This is the typical case for trades where people work with their hands, like the plumber under a sink or the hairdresser in the middle of a cut.
Out of hours
The call came in before opening, after closing, at the weekend or on a public holiday. Note the exact time: a call just after closing doesn't tell you the same thing as a call in the middle of the night. The former often come from customers calling as they leave their own work.
During another call
You were already on the phone. If call waiting is switched on, these calls appear in the log during your conversation: compare the time of the missed call with the times of the calls you answered. If call waiting is switched off, they go to voicemail and often leave just a message, or nothing at all.
Cases to set aside
Don't include identified sales calls, wrong numbers and family and friends in the useful total. Note them separately if you wish. An unknown number with no message, on the other hand, is still a missed call.
What the tally tells you, and what to do about it
After seven days, look at which column carries the most weight. Each one calls for a different response.
| If the busiest column is… | The problem | The first response |
|---|---|---|
| Opening hours, line free | Nobody has their hands free | Forwarding on no answer to someone who picks up |
| During another call | A single line for several callers | Forwarding when busy, or a reception that takes several calls at once |
| Out of hours | Your opening hours are not your customers' hours | A reception service that also answers in the evening and at weekends |
Two other readings are useful. The “Different callers” column shows how many people kept trying: someone who calls back three times has a real need. The “Message left” column, compared with the total, shows what your voicemail really holds on to; our comparison of AI voice agents and voicemail details this difference.
If your missed calls are concentrated at a few moments in the day, the peak hours guide offers a more detailed grid, slot by slot. And if you are a tradesperson, the plan to stop missing calls starts from this same tally to choose the right settings.
From number to value
The tally gives you a number and a breakdown, not yet a value. That is the next step: the guide to the cost of a missed call explains how to go from this number to an estimated loss, using the share of callers who don't call back and what a customer brings in. The calculator applies this calculation to the figures you enter, and sets it against the price of a plan.
Keep your sheet. It will serve as a point of comparison once you have changed something: a setting, the way you are organised or a tool.
When an agent answers for you
An AI voice agent does this tally for you. With Sayelo, every answered call produces an email summary, and the dashboard keeps the call history and statistics. The agent works as back-up for your team, never in its place: your phone can keep ringing first, and the agent takes whatever you miss. During the 14-day free trial, you can connect it to your current number by call forwarding, then compare with your week's tally. The plans and their minutes are detailed on the pricing page.
