Acquiring new members costs money. Google or social media advertising, promotions, events, your sales team’s time, marketing tools… Even when a gym does not have a large acquisition budget, bringing in new customers is rarely free.
The problem is that many gyms know how much they spend on marketing, but not how much it actually costs them to acquire each new member.
That is where CAC, or Customer Acquisition Cost, comes in. It is a particularly useful metric for understanding whether a gym’s acquisition strategy is sustainable and, above all, for identifying when you are investing more than you should to grow.
What is CAC for a gym?
CAC (Customer Acquisition Cost) tells you how much money a gym needs to invest, on average, to acquire one new customer.
The basic calculation is simple:
CAC = acquisition costs / number of new customers
For example, imagine that over the course of a month, a gym invests £1,200 in advertising, marketing tools and sales activities, and acquires 20 new members.
CAC = £1,200 / 20 = £60
The acquisition cost for each new customer would therefore be £60.
The formula is simple. Deciding which costs to include is not always quite as straightforward.
What should you include when calculating CAC?
One of the most common mistakes is to consider advertising spend alone.
If a gym invests £500 in campaigns and acquires 10 customers, saying that its CAC is £50 can be misleading if those campaigns are also supported by tools, staff or external providers involved in turning those contacts into customers.
Depending on the level of accuracy you need, your calculation could include:
- investment in Google Ads, Meta Ads and other channels;
- marketing and CRM tools;
- agencies or external professionals;
- promotions designed to attract new members;
- events and sales activities;
- a proportion of the cost of staff involved in acquisition and sales.
The important thing is to use the same criteria over time. There is little value in comparing your CAC in January with your CAC in June if one month includes advertising alone and the other includes all your sales costs.
What is a good CAC for a gym?
There is no universal figure.
A CAC of £80 could be excellent for one gym and too high for another. It mainly depends on how much revenue that customer generates and how long they remain a member.
Imagine two gyms that both pay £80 to acquire a new member.
At the first, membership costs £40 per month and members stay for an average of four months. At the second, membership costs £90 per month and average retention exceeds a year.
Although the CAC is identical, the profitability of those acquisitions is completely different.
That is why CAC should never be analysed in isolation. It makes far more sense to compare it with the value a customer generates throughout their relationship with the gym.
CAC and customer value: two metrics that should be analysed together
Customer Lifetime Value (CLV or LTV) estimates how much value a member generates throughout the time they remain a customer.
Looking at the relationship between these two metrics allows you to answer a much more useful question than simply “How much does it cost us to acquire customers?”:
Is it profitable to acquire customers at our current cost?
If acquiring a new member costs £70 but that customer generates several hundred pounds over the course of their membership, the cost may be perfectly sustainable.
However, if members leave quickly, even an apparently low CAC can become a problem.
This highlights an important point: reducing CAC does not always mean spending less on marketing.
You can also improve the relationship between acquisition and profitability by keeping members for longer.
How to reduce your gym’s CAC
Reducing Customer Acquisition Cost means acquiring more customers with the same resources or maintaining your acquisition volume while using fewer resources. To do that, you need to identify where efficiency is being lost in the process.
1. Identify which channels generate customers, not just leads
Having lots of leads does not necessarily mean you have an effective acquisition strategy.
One channel might generate 100 cheap leads but only two customers, while another generates 20 more expensive leads but converts ten of them into members.
If you only analyse cost per lead, the first channel might appear to perform better. Calculate CAC, and the conclusion could be completely different.
That is why it is important to know where each opportunity comes from and which ones ultimately become customers.
2. Improve your lead-to-member conversion rate
Before increasing your acquisition budget, look at what happens to the leads you already generate.
How long does it take between someone requesting information and receiving a response? Is there a follow-up process? Do you know which leads are still pending? Are potential customers being forgotten in an email inbox, spreadsheet or Instagram message?
Improving this part of the process can reduce CAC without generating a single additional lead.
If you invest £1,000 to generate 50 leads and five become customers, the CAC associated with that investment is £200.
If you can turn ten of those same 50 leads into customers, CAC falls to £100 without increasing your budget.
3. Make joining your gym easier
Every additional step between deciding to join and completing the sign-up process creates friction.
Waiting for a member of staff to be available, filling in paperwork manually, making a separate payment or having to visit the gym in person can all result in an interested prospect failing to complete their membership.
A simple sign-up process helps you make better use of the demand you have already generated.
It is not only about convenience for the new member. From a CAC perspective, it means losing fewer potential customers at the final stage of the funnel.
4. Encourage referrals
Word of mouth remains a particularly relevant acquisition channel for gyms and fitness businesses.
A satisfied member who recommends the gym to a friend can generate a new membership at a much lower acquisition cost than a paid advertising campaign.
That does not mean referrals are completely free. There may be discounts, incentives or promotions associated with a referral programme. Those costs can also be measured and compared with other channels.
This allows you to determine whether acquiring members through referrals really is more efficient than using advertising, events or other acquisition activities.
5. Reduce your reliance on aggressive promotions
Promotions can work extremely well for generating new memberships, but constantly relying on large discounts can distort the true cost of acquisition.
A free month, waived joining fee or introductory discount has a cost, even if it does not appear as expenditure on an advertising platform.
Attracting customers primarily through price can also affect how long they stay afterwards.
Promotions should therefore be analysed like any other channel: how many customers do they generate, how much do they cost and what happens to those customers afterwards?
6. Automate opportunity follow-up
As the volume of enquiries grows, relying on manual follow-ups makes it easier for potential customers to slip through the cracks.
One person requests information. Another asks for a trial. A third says they want to join next month. If those contacts are spread across emails, messages, notes and spreadsheets, some will inevitably receive no follow-up.
Centralising opportunities and automating certain actions allows your team to spend less time on repetitive tasks while reducing the number of leads lost during the process.
The goal is not to contact people more often for the sake of it, but to make the sales process more consistent.
Don’t try to reduce CAC at any cost
A lower CAC does not always mean a better strategy.
Imagine a gym removes its most expensive advertising channel and reduces its CAC from £75 to £50. On paper, that looks like an improvement.
But if that channel was also generating customers with higher membership values or longer retention, removing it could reduce overall profitability.
The same applies when reducing investment leads to a significant fall in new memberships.
The objective should not be to achieve the lowest CAC possible, but to find an acquisition cost that allows the gym to grow profitably and sustainably.
How to track CAC in your gym
Calculating this metric once provides limited information. Its real value comes from tracking how it changes over time.
You can start with a simple monthly overview:
Acquisition investment → leads generated → new customers → CAC
From there, it is worth breaking the results down by channel:
| Channel | Cost | Leads | New customers | CAC |
|---|---|---|---|---|
| Google Ads | £600 | 30 | 6 | £100 |
| Meta Ads | £400 | 40 | 4 | £100 |
| Referrals | £150 | 12 | 6 | £25 |
| Local event | £500 | 20 | 2 | £250 |
A table like this makes it much easier to identify where you need to investigate further.
However, you should not automatically conclude that the local event should be removed simply because it has the highest CAC. You would also need to look at the value those customers generate afterwards.
From CAC to more profitable customer acquisition
Customer Acquisition Cost makes acquisition more measurable than simply counting leads, followers or enquiries.
Knowing how much it costs to acquire a new member allows you to compare channels, identify inefficiencies and make better decisions about where to invest.
But CAC becomes truly useful when it is connected with the rest of the business: conversion, average membership value, length of membership, retention and customer value.
Because acquiring customers cheaply does not necessarily mean acquiring them well.
The goal is to acquire customers whose value to the gym justifies the effort and investment required to win them, while building an acquisition system that can remain sustainable as the business grows.
