How does this agency churn cost calculator work?

It runs one model twice, once at the churn rate you enter and once at half that rate, so you can see the cost and the prize side by side. You give it four numbers: how many active clients you have, what the average one pays each month, what share of clients you lose in a typical month, and what it costs you to acquire a replacement. From there it decays your client book month by month across a year, compares what a flat book would have billed against what a decaying book actually bills, and adds the acquisition spend you burn just to stay level. Nothing is stored and no email is required. Your inputs are encoded in the URL, so you can send the link to a partner or a co-founder and they will see exactly the same numbers.

What counts as the real cost of client churn?

Most operators only count the retainer that walked out the door, which understates the damage by roughly half. The real cost has two halves. The first is lost revenue: every month a client is gone is a month they are not billing, and that gap compounds across the rest of the year. The second is replacement cost: to keep the same client count you have to close new business you would otherwise have added on top, so every churned logo quietly converts a growth close into a break-even close. This calculator adds both, then expresses the total as an effective monthly drag on your MRR. That drag number is the honest one, because it tells you what percentage of your book is being spent on standing still.

What is a good monthly churn rate for an AI voice agency?

For small agencies selling monthly retainers, anything at or under 3% monthly logo churn is healthy, 4% to 6% is common and workable, and above 8% the business starts fighting itself. The intuition is easier in retention terms. At 3% monthly churn about 69% of your clients are still with you in twelve months and the average client stays roughly thirty-three months. At 8% that annual retention falls to around 37% and average client life drops to twelve and a half months, so you are rebuilding most of the book every single year. Voice agencies tend to sit slightly higher than general marketing agencies early on, because clients judge the agent on call outcomes within the first sixty days rather than waiting on a quarterly report.

Why does churn hurt more than a slow month of sales?

Because a slow sales month is a one-time gap while churn is a compounding subtraction. If you miss a close in March you are one client behind in March. If you lose a client in March you are one client behind in March and in every month after it, and you also owe yourself the acquisition cost of replacing them. The calculator makes this visible by showing how many new closes a year you need purely to hold your current client count. For an agency of ten clients at 5% monthly churn that is six closes a year before a single unit of growth. Founders usually respond to that number by moving effort from top-of-funnel to onboarding and reporting, which is almost always the cheaper fix.

What actually reduces churn in a voice agency?

Three things, in order of impact. First, proof: clients cancel when they cannot see what the agent did, so a monthly view of calls handled, appointments booked, and calls recovered after hours turns a line item into an obvious keep. Second, onboarding speed: an agent that goes live in days holds attention, while one that drifts for six weeks loses the sponsor who signed the deal. Third, margin room: agencies eating unpredictable per-minute overage tend to under-serve accounts to protect their own margin, which shows up as churn a quarter later. Hermes covers all three as the operating layer under the agency, with CRM, campaign orchestration, transparent client billing, and a white-label portal in one plan, and a first agent typically live in 72 hours.

How does my stack affect churn and the cost of replacing clients?

Every tool in the stack is a place where reporting breaks, onboarding stalls, and margin leaks, and all three feed churn. Running Retell or Vapi for voice, GoHighLevel for CRM, Zapier for automation, Stripe for billing, Twilio for telephony, and a developer to glue it together means client-facing proof lives in five places and rarely reaches the client at all. Consolidating removes the maintenance tax and makes reporting a default rather than a project. Hermes runs from $149 a month for Starter with 300 included minutes, $399 for Business with 1,000, or $699 for Agency with 2,000, plus $0.24 per overage minute, all under your brand. Your clients never see the word Hermes. Book a 20-minute walkthrough with the numbers you just entered.

free tool

What is churn actually costing your agency?

Losing a client costs you the retainer and the cost of replacing them. Enter your client count, price, churn rate, and CAC to see the annual number, the monthly drag on your book, and what half the churn would be worth.

/ active clientsPaying retainer clients today. Pilots and free trials do not count./ average client price (USD per month)Recurring retainer only. Leave out setup fees and one-off project work./ monthly client churn (%)Share of clients you lose in an average month. Two lost out of forty is 5%./ cost to acquire a replacement (USD)Ad spend, tooling, commission, and your own time to land one new client.

/ annual cost of churn

$51,363

$4,280 a month of effective MRR drag, 29.7% of your book

Revenue lost

$47,043

Replacement CAC

$4,320

Clients to replace

4.8

Annual retention

54.0%

Avg client lifetime

20 mo

LTV to CAC

40.0x

If you cut churn in half

$23,543 back

At 2.5% monthly churn your annual cost drops to $27,820, average client life goes from 20 to 40 months, and LTV goes from $36,000 to $72,000.

Left alone, 8 clients decay to 4.3 in twelve months. Standing still costs you 4.8 new closes a year before you grow at all.

Book a 20-min walkthrough to cut this number, by fixing the reporting and delivery gaps that drive churn in the first place. Want the full breakdown for your agency? Book 20 min and bring these inputs.

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how it works

Churn is not a lost retainer. It is a lost retainer plus a closed deal.

When an agency owner adds up churn, the usual math is the monthly retainer times the months remaining in the year. That captures maybe half of it. The other half is the acquisition cost of the replacement, because holding your client count flat means closing new business that would otherwise have been growth. A ten-client book at 5% monthly churn needs six new closes a year before it grows by a single client. Those six closes carry real cost in ad spend, tooling, commission, and your own selling time, and none of that cost shows up anywhere on a revenue chart.

This calculator adds both halves and then converts the total into an effective monthly drag, expressed as a percentage of your current MRR. That percentage is the most useful figure on the page, because it tells you what share of the business is being spent to stand still. It also runs the same model at half your churn rate, so the value of a retention fix is a dollar figure rather than a feeling. For most agencies in the $5,000 to $30,000 a month range, halving churn is worth more than adding two new clients, and it is usually cheaper to do.

The fixes tend to be operational rather than commercial. Clients cancel when they cannot see what the agent did, when onboarding drags past the point where the sponsor stays engaged, or when unpredictable per-minute costs push the agency to under-serve the account. Hermes is the operating platform underneath the agency: deploy and manage voice agents under your own brand with CRM, campaign orchestration, transparent client billing, and a white-label portal in one plan, from $149 a month with 300 included minutes, $399 for 1,000, or $699 for 2,000, plus $0.24 per overage minute. Your clients never see the word Hermes. Enter your real numbers above, then bring them to a 20-minute walkthrough.

frequently asked

Common questions.

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What is churn actually costing your agency?

Churn is not a lost retainer. It is a lost retainer plus a closed deal.

Common questions.

Run your agency on Hermes.

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