What is customer acquisition cost?
Every customer comes at a cost. Whether you’re running Facebook Ads, collaborating with influencers, or investing in SEO, you’re spending money to acquire new customers. Customer Acquisition Cost (CAC) measures exactly how much it costs your business to gain one paying customer.
CAC is one of the most important ecommerce metrics because it helps answer a simple question:
“Am I spending too much to acquire customers compared to the revenue and profit they generate?”
Tracking CAC allows Shopify merchants to make smarter marketing decisions, allocate budgets efficiently, and scale sustainably.
The formula is straightforward:
Customer Acquisition Cost = Total Marketing & Sales Expenses ÷ Number of New Customers Acquired
For example, imagine your Shopify store spends $7,000 on Facebook Ads, Google Ads, influencer partnerships, email marketing software, and creative production during one month. If those campaigns generate 200 first-time customers, your CAC is $35. In other words, every new customer costs your business an average of $35 to acquire.
While the calculation is simple, many merchants underestimate their true CAC by only including advertising costs. A more accurate calculation should also account for agency fees, affiliate commissions, software subscriptions, marketing salaries, and other acquisition-related expenses.
Why Customer Acquisition Cost matters?
CAC is much more than a marketing metric – it is a measure of business efficiency. It helps you determine whether your marketing strategy is sustainable and whether your advertising budget is being spent wisely.
A consistently rising CAC may indicate increasing competition, declining advertising performance, or an ineffective conversion funnel. On the other hand, a decreasing CAC often suggests that your marketing efforts are becoming more efficient.
Monitoring CAC also allows merchants to answer important business questions. Are paid campaigns generating profitable customers? Which marketing channels deserve more investment? Can the business afford to scale its advertising budget? Without knowing your acquisition cost, these decisions become little more than educated guesses.
CAC Doesn’t Tell the Whole Story
Although CAC is important, it should never be evaluated in isolation.
Consider two Shopify stores. Store A acquires customers for $20 each, while Store B spends $45 per customer. At first glance, Store A appears to have the better marketing performance.
However, Store B sells premium products with higher margins, larger average order values, and customers who make repeat purchases throughout the year. As a result, each customer generates several times more profit than they cost to acquire. In contrast, Store A’s customers rarely purchase again, making its seemingly “better” CAC far less valuable.
This example highlights an important lesson: a low CAC does not automatically mean your business is more profitable. Instead, CAC should always be analyzed alongside other ecommerce metrics.
The Relationship Between CAC and Customer Lifetime Value
Customer Lifetime Value (CLV) measures the total revenue a customer generates throughout their relationship with your business. Together, CLV and CAC provide one of the clearest indicators of business health.
Many ecommerce experts recommend maintaining a CLV:CAC ratio of at least 3:1. This means each customer should generate approximately three dollars in lifetime value for every dollar spent acquiring them. If the ratio is significantly lower, your acquisition strategy may not be sustainable in the long run.
For businesses with subscription products or strong customer loyalty, a higher CAC may be perfectly acceptable because repeat purchases eventually offset the initial acquisition cost.
Read more about Customer Lifetime Value: Customer Lifetime Value – GoProfit
CAC, ROAS, and Profit Margin
Another common mistake is relying exclusively on Return on Ad Spend (ROAS).
A campaign can produce an impressive ROAS while still generating very little profit if product costs, shipping expenses, or discounts are high. Likewise, campaigns with lower ROAS may actually contribute more profit if they attract customers with higher lifetime value.
This is why Shopify merchants should evaluate marketing performance using multiple metrics rather than relying on one number alone. CAC explains acquisition efficiency, ROAS measures advertising effectiveness, and profit margin ultimately determines whether the business is making money.
Learn more about marketing performance metrics: Conversion rate – GoProfit
What is Considered a Good CAC?
There is no universal benchmark for Customer Acquisition Cost because every business operates differently. Luxury brands, subscription businesses, and stores selling high-ticket products can generally support much higher acquisition costs than businesses with inexpensive products and thin margins.
Instead of chasing an industry average, merchants should focus on improving their own performance over time. If your CAC continues to decline while maintaining healthy profit margins and customer lifetime value, your marketing strategy is moving in the right direction.
Tips for reducing CAC
1. Enhance your site’s SEO
Renaissance Digital Marketing aimed to lower its CAC by focusing on search engine optimization (SEO), which involved improving content, technical SEO, and building backlinks. “We saw a 45% increase in organic traffic over six months,” says managing director Doug Darroch. “This led to a 30% drop in CAC, as organic leads are generally cheaper compared to paid channels.”
2. Identify your most efficient marketing channels
Nautilus Marketing reevaluated its marketing strategy by analyzing which channels were most cost-effective. By reallocating funds to top-performing digital ads and cutting spending on less effective ones, they optimized their budget. “These adjustments led to a 15% reduction in CAC over six months,” says Tom Jauncey, co-head of Nautilus Marketing.
3. Target high-value customer segments
Nautilus Marketing further shortened its CAC payback period (the time to recover acquisition costs) by focusing on customers likely to spend more or remain loyal. “Targeting higher-value segments reduced our CAC payback from six to four and a half months,” says Tom. To do this, use segmentation tools to profile customers and customize marketing strategies to cater to the preferences of these valuable groups.
FAQ
What is Customer Acquisition Cost (CAC)?
Customer Acquisition Cost refers to the total amount spent to bring in a new customer. This encompasses all costs related to sales, marketing, and any other efforts that contributed to turning a potential lead into a paying customer.
How is Customer Acquisition Cost calculated?
To determine CAC, add up all the sales and marketing expenses for a given period. Then, divide this sum by the number of new customers acquired during that timeframe. This will give you the average cost to gain a new customer.
What expenses should be factored into the total marketing spend for CAC?
Include costs such as marketing tools and software, employee salaries for marketing teams, advertising expenses, the cost of discounts and promotions, content creation, and any other sales-related expenses that helped with marketing during the specified period.
