Every month, you spend money on advertising to attract new customers. But have you ever calculated exactly how much that costs you per customer? The well-known rule of thumb is that new customers cost five times as much as existing customers. But what does that mean specifically for your business?
In this post, you'll find an easy-to-follow calculation example, along with a clear comparison of customer acquisition and retention costs. This will help you allocate your marketing budget more effectively.
What are customer acquisition costs (CAC)?
Customer acquisition cost, or CAC for short, indicates how much you spend on average to acquire a new customer. The abbreviation stands for Customer Acquisition Cost.
CAC = Total Acquisition Cost ÷ Number of New Customers Acquired
- Online Advertising (Google Ads, Social Media Ads)
- Print Ads, Flyers, Poster Advertising
- Discounts and promotions specifically for new customers
- Personnel Costs in Sales
- Agency and Consulting Fees
- Costs for events, trade shows, or partnerships
Many companies don't even know their CAC. Without this figure, it's nearly impossible to assess whether a Customer Acquisition Efforts Are Truly Worth It.
How much does customer retention cost?
Retention costs, sometimes also referred to as customer retention costs, include everything you invest in existing customers.
- Loyalty Program (License, Operation, Rewards)
- Communication (newsletters, push notifications, email marketing)
- Customer Service and Complaint Management
- Personalization and CRM Management
- Exclusive Offers for Regular Customers
The difference matters: Many of these costs are fixed or degressive. They do not increase proportionally with the number of customers. A loyalty program does not cost five times as much for 500 active users as it does for 100.
Sample Calculation: Customer Acquisition vs. Retention for a Café
Here's an example to illustrate the point: A medium-sized café with one location highlights the differences.
| Cost Item | New Customer Acquisition | Existing Customer Retention |
|---|---|---|
| Online Advertising (Google, Social Media) | 800 € | N/A |
| Flyers & Printed Materials | 200 € | N/A |
| New Customer Discount (20 % on first order) | 300 € | N/A |
| Loyalty Program (Monthly License) | N/A | 150 € |
| Push Notifications and Newsletters | N/A | 50 € |
| Rewards and Redemptions | N/A | 200 € |
| Personnel Expenses (pro rata) | 200 € | 100 € |
| Total Monthly Costs | 1.500 € | 500 € |
| Customers Reached | 60 new customers | 200 active regular customers |
| Cost per person | 25 € per new customer | €2.50 per regular customer |
In this example, the commitment per capita is ten times cheaper than customer acquisition. And regular customers generally spend more, too.
What are the additional benefits of this bond?
Let's do some more math. According to the DACH Loyalty Report 2026, customers who participate in a rewards program spend an average of 27.9 % more ... With an average receipt total of €8, that makes a clear difference.
- Without a loyalty program: 200 regular customers, 4 visits per month, €8. That adds up to €6,400 in monthly revenue.
- With a loyalty program: 200 regular customers, 4 visits per month, €10.23. That amounts to €8,184 in monthly revenue.
- Difference: an additional €1,784 in monthly revenue.
After deducting the €500 commitment fee, there remains a Net additional income of €1,284 per month. This figure does not even include additional visits resulting from stronger customer loyalty.
Customer Lifetime Value: The Long-Term Perspective
Looking at things on a monthly basis doesn't tell the whole story. What really matters is the customer lifetime value, or CLV for short. It reflects the total value of a customer relationship over its entire duration.
CLV = Average Revenue Per Visit × Visits Per Month × Retention Period in Months
- Without a loyalty program: 8 € × 3 visits × 12 months = 288 €.
- With the loyalty program: €10.23 × 4 visits × 24 months = €982.
With a loyalty program, the CLV is more than three times higher. Loyal customers visit more often, spend more, and stay longer. You can find more sample calculations in the article on Customer Lifetime Value.
CLV and CAC yield an important ratio. A healthy CLV-to-CAC ratio is at least 3 to 1. If it’s lower than that, too much of the budget is being spent on customer acquisition.
Why Existing Customers Are More Profitable
Lower costs are only part of the equation. Existing customers are also more valuable from a business perspective for other reasons.
Higher Expenditures
The DACH Loyalty Report 2026 shows: 26,2 % Of those surveyed, more have been buying from the same company since they started using a rewards program. And 58,5 % They make more targeted purchases in order to earn loyalty rewards.
Lower price sensitivity
Loyal customers shop around less. They’re familiar with what you offer, trust the quality, and are more relaxed about price changes. A new customer compares three providers. A regular customer comes straight to you.
Recommendation
15,9 % According to the DACH Loyalty Report 2026, respondents are more likely to recommend a company since they started using a rewards program. Every recommendation is essentially free customer acquisition.
Less Need for Service
Existing customers are familiar with your product and your processes. They ask fewer questions, require less onboarding, and generate fewer support costs.
If you focus only on new customers, you'll overlook your most profitable target group: your own regular customers.
Five Strategies for an Efficient Retention Budget
These five strategies show you how to use your relationship budget effectively.
1. Introduce or optimize a loyalty program
A digital customer loyalty program serves as the structured framework for all other initiatives. It provides data, opportunities for communication, and tangible added value. The costs are predictable and, as the sample calculation shows, are quickly recouped.
2. Increase the frequency of communication
Many companies don't reach out to their existing customers often enough. Yet regular, relevant communication is one of the most cost-effective ways to build customer loyalty. A push notification costs practically nothing, but it can prompt the next visit.
3. Personalization Instead of a One-Size-Fits-All Approach
Invest in segmenting your customers. Those who send targeted offers instead of generic messages achieve better redemption rates at the same cost. According to the DACH Loyalty Report 2026, it is expected that 61 % personalized offers for customers.
4. Quick Rewards Instead of Long Grinds
82,4 % According to the DACH Loyalty Report 2026, consumers want benefits that are immediately visible and can be redeemed right away. Low redemption thresholds drive more activity without incurring higher costs.
5. Measure and Optimize Success
Track your Customer Loyalty KPIs: Repurchase rate, average receipt value, redemption rate, and churn rate. This is how you can identify which measures deliver the greatest return.
Budget Allocation: How Much for Customer Acquisition, How Much for Customer Retention?
There is no one-size-fits-all formula, but there are general guidelines. For SMEs with an existing customer base, a ratio of 40 % for new business development to 60 % for customer retention is often a good starting point.
| Company Stage | Share of New Business | Binding Content |
|---|---|---|
| Start-up / Market Entry | 70 to 80 % | 20 to 30 % |
| Growth phase | 50 to 60 % | 40 to 50 % |
| Well-established company | 30 to 40 % | 60 to 70 % |
Important: The boundary is not rigid. A good loyalty program also helps attract new customers, for example through referrals. According to the DACH Loyalty Report 2026, a company with a bonus program has an impact on 67,7 % of the respondents, more modern and up-to-date.
Conclusion
Customer retention is usually not only less expensive than acquiring new customers—it’s also more profitable. Existing customers buy more, buy more often, and cost less to serve. That doesn’t mean you should neglect customer acquisition. But it’s worth regularly reviewing the balance between the two and making targeted investments in customer retention.
Frequently Asked Questions
Is the rule of thumb true: that acquiring new customers costs five times more than retaining existing ones?
This rule of thumb is based on various studies and is cited across industries. In some industries, the factor is three; in others, it’s seven or higher. This depends on the sales channel, product complexity, and competition. More important than the exact number is the underlying message: Retaining existing customers is almost always significantly less expensive than acquiring new ones.
Can I simply reallocate my acquisition budget to retention?
It won’t happen overnight, and it won’t be a complete shift. You’ll still need new customers to grow and offset natural attrition. A gradual shift makes more sense. For example, test how increasing your customer retention budget by ten to twenty percent affects your repurchase rate and average transaction value.
What counts as acquisition costs?
This includes all expenses intended to attract new customers, either directly or indirectly: online advertising, print materials, sales staff, new-customer discounts, trade shows, and agency fees. It also includes the portion of your team’s working hours dedicated to acquiring new customers. Many small and medium-sized businesses underestimate their true customer acquisition costs because they don’t factor in personnel expenses.
How do I calculate my customer lifetime value?
The simplest formula is: average revenue per transaction multiplied by the number of transactions per year multiplied by the average customer retention period in years. For a more accurate picture, you can use contribution margins instead of revenue. CLV shows you the maximum amount you can spend on customer acquisition so that a new customer pays off in the long run.
How does customer loyalty affect profit margins?
Positive, for three reasons. First, the cost of retaining customers per person is lower than the cost of acquiring new ones. Second, regular customers spend more per purchase. Third, service costs decrease because existing customers require less support. Together, these effects can significantly increase the overall margin.
Are there industries where customer acquisition is less expensive than customer retention?
In industries where repeat purchases are very rare—such as moving companies—the focus is more on customer acquisition. But even there, customer loyalty in the form of referrals is worthwhile. In most industries that involve regular customer contact—such as retail or the restaurant industry—customer loyalty is clearly more effective.
