How Many Customers Do Missed Calls Cost You? Loss Calculator

See also: Recovering missed leads | Smart voicemail vs. traditional voicemail

TL;DR: You can estimate the monthly loss from missed calls with a formula: missed calls per day × working days × share of calls that end in an order × average order value. Example with assumed numbers: 5 × 20 × 20% × $500 gives $10,000 of potential revenue a month. This is an upper estimate, because some callers will call back or leave a message, so use your own figures.

The numbers in the examples are assumed and only show how the calculation works. Use your own figures.

You run a service business, such as plumbing, electrical work or a hair salon. The phone rings, but your hands are full. You reject the call thinking "I'll call back in a moment". When you call back hours later, the customer may already have booked someone else.

Not every missed call is a lost customer, but some are. Below you can work out what that may cost at your own numbers.

How to Count Your Missed Calls

Before you use the formula, collect three numbers from your own business:

Missed calls per day. Check the call log on your phone for a typical week and divide the number of missed calls by the number of working days. Leave out numbers that called back on their own, and known spam.
Share of calls that end in an order. Take the answered calls from new customers last month and count how many became an order.
Average order value. Divide the revenue from orders in recent months by the number of orders.

We don't quote national percentages, because we didn't find a current study with a described method. Your own numbers will tell you more than an average from other industries.

Loss Calculator — How Much Are You Really Losing?

The formula has four parts. Put your own numbers in place of the example ones.

Formula:

Monthly loss = missed calls per day × working days × share of calls that end in an order × average order value

Example (assumed numbers, not a real business):

Missed calls per day: 5
Working days per month: 20
Share of calls that end in an order: 20%
Average order value: $500

Calculation:

5 × 20 = 100 missed calls a month
100 × 20% = 20 orders that might have happened
20 × $500 = $10,000 of potential revenue a month

At 10% the result falls to $5,000, and at 30% it rises to $15,000. This is an upper estimate: some callers will call back on their own, leave a message, or aren't new customers. The result shows how much you might lose, not how much you certainly lose.

What Happens After a Missed Call

A sample sequence (an illustration, not a measurement):

Right away: The customer hears: "beep beep beep" (busy). Emotion: Frustration. "They don't have time for customers?"

A moment later: The customer returns to Google. Action: Calls the next number on the list.

A few minutes later: The competition answers: "Good morning, Company Y, how can I help?" Result: The customer remembers the competitor's brand as "the one who answered".

A few hours later: You call back an unknown number. Result: "Thanks, I already arranged with someone else."

Outcome: the order, and often a regular customer, go to the company that answered.

How to Lose Fewer Enquiries

Decide Who Calls Back and When

Name one person and fixed callback times, for example during a break and at the end of the day. The sooner you call back, the smaller the chance that the customer books elsewhere.

Ask for a Message With Details

Your voicemail greeting can ask for a name, a description of the matter and a convenient time. Example: "Hello, this is [company name]. I can't take your call right now. Please leave your name, a short description of what you need and the best time to call you back." More wording in our voicemail greeting examples.

Turn Messages into Text

In Heilo, Heilo Voicemail does this:

You set up forwarding at your carrier to the Heilo number for when you don't answer and, optionally, when your phone is unavailable. Our guide to setting up call forwarding to an answering machine shows how.
A customer calls your number and you don't pick up.
The carrier forwards the call to Heilo and the caller hears your greeting.
If they leave a message, Heilo saves the recording, prepares a transcript and a summary, and extracts the details given, e.g. name, service and date.
Once notifications are on, you get an SMS with the caller's details, the topic and a link. On the "Customer potential" card in the dashboard you can record your own 1–10 rating of the enquiry.
You call back knowing what it is about.

Heilo does not talk to the caller and does not answer calls for you: it takes only the calls your carrier forwards to it, and only some callers leave a message. You can also set up an automatic SMS to the caller, for example with a link to a form; we don't guarantee SMS delivery.

Teams: Every Rep With Their Own Number

If several people take customer calls, Heilo Line gives each rep a +48 business number. Calls through that number are recorded automatically, and you can call back from the call list in the dashboard with the “Call via Heilo” button (+48 numbers only). The plan is described on the call assistant page.

How Much Does Voicemail Cost with Heilo?

Heilo has three plans, Heilo Voicemail, Heilo Select and Heilo Line, priced per number per month; prices are net, billed monthly, with VAT added at payment. Heilo Voicemail covers messages after missed calls: recording, text, summary and SMS notification. Heilo Line includes 6 hours of recorded calls per number in each billing period; each extra hour is billed per minute at the rate on the pricing page and added to the next invoice. Heilo Voicemail and Heilo Select carry an indicative limit of 500 recorded minutes per number per month that never blocks calls. Check your carrier's charges for forwarded calls separately.

Compare the result with the plan price on the pricing page, and ask whether one extra order a month would cover it.

If you also want to record the calls you answer, there are two higher plans. With Heilo Select you keep your number and add Heilo to a chosen call through a conference call; Heilo records from the moment it joins, and your phone and carrier must support conference calling. Voicemail is included. Heilo Line is a +48 business number for sales reps and teams, one for each rep. Inbound calls and outbound calls placed with “Call via Heilo” are recorded automatically: Heilo produces a transcript, a summary and tasks, and the call coach gives feedback on two-sided calls with a transcript, showing what went well and what to improve. Once you set up an integration, results reach your CRM through the API, webhooks, Zapier or Make. The plan is described on the call assistant page.

Verified: 20 October 2026

Summary

Missed calls can cost more than you expect, but the result depends on your own numbers, not on general statistics. Work it out with the formula in this article, then decide whether fixed callback times are enough or you need voicemail that gives you text. In Heilo that is Heilo Voicemail, and sales teams have Heilo Line.

See Heilo business voicemail

FAQ – Frequently Asked Questions

How many customers don't call back after a missed call?

We don't quote a single figure, because we didn't find a current study with a described method. Check it yourself: for two weeks, write down the missed numbers and mark which ones called back or left a message.

How much does Heilo cost?

Each of the three plans, Heilo Voicemail, Heilo Select and Heilo Line, is priced per number per month; prices are net, billed monthly, with VAT added at payment. Details are on the pricing page.

Does Heilo answer the phone for me?

No. When you don't answer, your carrier forwards the call to Heilo, and the caller hears your greeting and can leave a message. Heilo doesn't talk to the caller and doesn't book appointments. It works only if you have set up forwarding at your carrier.

How do I check whether voicemail changed anything?

Compare the month before the change with the month after it: the number of missed calls, the number of messages left and the number of orders from the phone. We don't promise a particular result, because it depends on your industry, your greeting and how quickly you call back.