What does a missed call cost a vet clinic? (With a calculator)

By the Tilly editorial team · Updated October 7, 2026

A missed call costs your clinic the visit it would have booked, but only when the caller doesn't call back. To estimate the cost of missed calls at a veterinary clinic, multiply your missed calls a month by the share that were booking calls, by the share of those callers you assume don't call back, and by your average visit value. This article walks through each input, shows three example clinics, and is honest about what the number leaves out. At the end you can try it with your own numbers.

The short answer: missed calls × bookings × callers who don't call back × visit value

The formula has four parts. Each one is a number you can find or estimate for your own clinic:

1. Missed calls a month: calls per day, times days open, times the share of calls that go unanswered.
2. The share that were bookings: of those missed calls, how many were people who wanted an appointment.
3. The share who don't call back: of those booking callers, how many never tried again and went elsewhere. This is an assumption, not a statistic. Nobody has published a reliable figure for it.
4. Average visit value: what a typical visit is worth to your clinic.

Multiply them and you have an estimated monthly loss. Multiply by twelve for a year. That's all the missed-call calculator does, with the working shown.

How many calls do clinics miss? Here's the one published figure we use:

That figure is MissedCalls.help data reported by Today's Veterinary Business. It's a starting point. Your own clinic may be better or worse, and your own number is always the one to use.

Each input explained, and where to find your number

Calls per day

Count inbound calls on a typical weekday. Your phone provider's call log or online portal usually shows this. If it only gives a monthly total, divide by the days you're open. Ignore outbound calls your team makes.

Days open per month

The calculator assumes 22 days a month, which fits a clinic open on weekdays. If you open on Saturdays, add them. If you want to count after-hours calls too, you can treat your whole month as open days, but then use your after-hours missed share, which is usually much higher.

Share of calls missed

A missed call is one that rang out, hung up while waiting in a queue, or went to voicemail. The calculator starts at 25%, at the low end of the range above. Many phone systems don't report this directly. Look for "unanswered", "abandoned" or "missed" in your call reports. If you can't find it, a free missed-call audit measures it for you.

Share of missed calls that were bookings

Not every call is a booking. Some are refill requests, results questions, directions or hours. The calculator assumes 40% of missed calls were people wanting an appointment. To check your own figure, tally a week of answered calls by reason. Missed calls tend to follow a similar mix, though calls at opening time often lean toward bookings.

Share of missed callers who don't call back

This is the most uncertain input, so we say it plainly: the calculator's starting value of 60% is our assumption, not a statistic. Some callers try again a few minutes later. Some leave a voicemail. Some book with the clinic down the road. Change it if you know your own pattern. You can test it by matching the numbers of missed callers against later inbound calls and new bookings over a week or two. That's one of the things the audit looks at.

Average visit value

Use your own average transaction value from your practice software (PIMS). Most systems report it by month or by visit type. The calculator starts at $185. That default is Tilly's starting assumption, not a published benchmark, so replace it with your own average as soon as you can.

Two inputs the calculator adds

The calculator also asks how many locations you have and which Tilly plan you're looking at, to show a plan cost and a rough payback period. It also estimates how much of the lost revenue could be recovered if those calls were answered, using a capture share of 70%. That's another assumption: even an answered call doesn't always become a booking. Plan prices come from our pricing page.

Three example clinics

To show how the formula behaves, here are three illustrative clinics. These are example inputs, not data about real clinics:

• A one-vet rural clinic with a modest call volume and a lower average visit value than the default.
• A three-vet suburban clinic with a busier phone line, using all the calculator defaults.
• A five-site group with calls counted across all five locations, open on Saturdays as well, and a higher average visit value.

Reading the table

Each row runs the same formula. The calls column is the only input that changes between the suburban clinic and the defaults. The rural clinic also uses a lower visit value, and the group uses more open days and a higher visit value, to show how those inputs shift the result. The missed calls column is calls per day, times days open, times the missed share. The lost bookings column applies the booking share and the call-back assumption. The revenue columns multiply by visit value.

Notice that the group's figure grows faster than its call volume alone would suggest. More open days and a higher visit value stack on top of the extra calls, because each input multiplies the others. That's also why a group should look at each location separately: one busy site can account for most of the total.

How sensitive is the answer?

Every input in the formula is a multiplier. That has a simple consequence: if you double any one input, the result doubles. If you halve one, the result halves. No single input matters more than another in the arithmetic. What differs is how sure you are of each one.

• Calls per day and days open are usually the most reliable, because your phone system counts them.
• The missed share is often a guess until you measure it. If your real figure is lower than the default, your result drops in proportion. If it's higher, which is common at lunchtime and after hours, it rises.
• The booking share varies with your call mix. A clinic that handles refills mostly online will see a higher share of booking calls on the phone.
• The call-back share is the weakest input. If most of your missed callers do try again, the cost falls sharply. If your area has several clinics close together, fewer may come back.
• Visit value moves the result directly. A clinic with a lot of dental or surgical work will see a higher figure than one focused on wellness visits.

The honest way to use the estimate is to change the input you doubt most and see whether your decision changes. If even a cautious set of numbers shows a cost worth acting on, you have your answer. If the result only looks large with generous assumptions, measure before you spend.

What the formula leaves out

The formula counts one visit per lost booking. That keeps it simple, but it misses some real costs, and in some cases it overstates the loss.

Client lifetime value

A new client who books a first visit may stay for years and bring their other pets. The formula counts only that first visit, so for new-client calls the real loss is usually larger. We don't add a number for it, because client lifetime varies too much between clinics to estimate fairly.

Staff time

Missed calls come back as voicemails to return and callbacks that don't connect. Returning a call often takes longer than answering it in the first place. That time isn't in the formula.

Stress

A phone that rings while your team is with a client is a constant low-level pressure. It wears people down. No formula prices that well, but it matters when you weigh your options.

Calls that aren't bookings

The formula only values missed booking calls. But a missed refill request or results question doesn't vanish either. The client calls again, often at a busier moment, or arrives at the desk frustrated. Those repeat calls add to the load that caused the first missed call. They don't show up as lost revenue, but they show up in your team's day.

Where the estimate may be too high

If your schedule is full for weeks, an extra booking request may only replace another one. Some missed callers would have booked short, low-value visits. Some call back from a different number. Be fair to your own situation. When the schedule is full, answering more calls is worth more in client experience and staff time than in extra visits.

For the bigger picture, including how phone services bill, capacity planning and measuring return over 90 days, see our guide to what your phones are worth. If you want to see which calls become bookings once they're answered, our call reports show calls answered, bookings made and an estimate of recovered revenue with the method behind it.

Try it with your numbers

Put in your calls per day and change any assumption you doubt. Nothing is saved unless you ask us to email the result.

missed_calls_month  = calls_per_day × days_open × missed_pct
lost_bookings_month = missed_calls_month × booking_share × no_callback_share
lost_revenue_month  = lost_bookings_month × visit_value
lost_revenue_year   = lost_revenue_month × 12
recoverable_month   = lost_revenue_month × capture_share
plan_cost_month     = plan price per location × locations
payback_days        = ceil(plan_cost_month ÷ (recoverable_month ÷ 30.4))

Once you have a result, a few next steps help:

• Check the inputs you guessed. Swap in your real call volume and your own average visit value from your practice software.
• Try a cautious version. Lower the missed share and the call-back assumption and see whether the cost still matters to you.
• Look at when calls are missed. Lunchtime, the first hour after opening and after-hours calls often need different fixes.
• Measure before you buy. Whatever you decide, record a baseline first so you can see what changed.

If you'd rather know your real numbers than estimate them, ask for an audit. We'll measure how many calls you miss, when they happen and what they're likely worth.