Customer Profitability Analysis
Customer profitability analysis measures the net profit each customer generates after all costs to serve them – not just gross margin. In most portfolios we model, 20% of customers create 150-300% of total profit while 20-30% quietly destroy it. The question is never whether this is happening in your customer base. It’s where.
Why gross margin gets it wrong
Your highest-gross-margin customer may be the worst deal you have. Gross margin stops at product cost. It ignores everything that comes after: rush deliveries, split shipments, returns, year-end rebates, weekly sales visits, 120-day payment terms, the support hours nobody logs against an account.
These costs to serve are what separate two customers with identical revenue into opposite profit outcomes – and because almost no system assigns them to customers, the portfolio gets managed on the wrong metric: volume.
How it’s calculated – a worked example
Customer profitability = revenue − product cost − cost to serve. TDABC computes the third term with time equations over data you already have. Two customers, same revenue:
| Customer A | Customer B | |
|---|---|---|
| Annual revenue | €500,000 | €500,000 |
| Gross margin (35%) | €175,000 | €175,000 |
| Orders / year | 24, scheduled | 310, urgent & split |
| Cost to serve (TDABC) | €38,000 | €196,000 |
| Net profit | €137,000 (27%) | −€21,000 (−4%) |
On the sales report, A and B are twins. In reality, B consumes A’s profit – and is probably being treated as a star account, with an extra discount coming at the next renewal.
The whale curve: your portfolio in one picture
Rank customers from most to least profitable and plot cumulative profit, and you get the whale curve. The hump rises fast – a minority of customers builds 150-300% of final profit. Then the tail gives it back. The gap between the peak and where you end the year is margin you already earned and then destroyed.
What to do about the tail (it’s not “fire your customers”)
- Reprice – make price reflect true cost to serve: surcharges for urgency, order minimums, payment terms with teeth;
- Redesign the service – change how you serve: consolidated deliveries, online ordering, self-service support. Customer B above turns profitable with one weekly delivery;
- Renegotiate or release – the last resort, with numbers on the table. Most unprofitable customers would rather change behaviour than change supplier.
The order matters. Companies that lead with “fire the tail” destroy revenue they could have fixed. Companies that never act subsidise their competitors’ best customers with their own best customers’ profit.
What a consulting engagement adds
The concept is simple; the allocation is not. Getting cost to serve right means modelling order handling, logistics, commercial time, technical support and financing cost per customer – without drowning in detail. That is TDABC’s home turf, and ours:
- Profit Check (free, 5 minutes) – scores your current cost-management maturity and tells you if you’re ready for this analysis;
- ProfitAudit 360 (3 weeks, fixed fee) – a TDABC model on your real data, the whale curve of your portfolio, and a margin roadmap with reprice/redesign/release actions quantified per account;
- Live model (optional) – the analysis recalculates nightly in CostCtrl, so customer profitability becomes a managed number, not an annual study.
Frequently asked questions
What is customer profitability analysis?
It is the measurement of net profit per customer after all costs – product cost plus the cost to serve (logistics, commercial, administrative, financing). It distinguishes the customers who create value from those who destroy it, which gross margin alone cannot do.
How is it different from gross margin analysis?
Gross margin stops at product cost. Customer profitability also deducts the cost to serve, which in service-intensive businesses reaches 25-40% of revenue – and is what separates customers with identical revenue into opposite profit outcomes.
How many customers are typically unprofitable?
Across the models we have built, 20-30% of a typical portfolio destroys value – and they are rarely the accounts the sales team suspects. The pattern holds in manufacturing, distribution, logistics and healthcare.
What data does it require?
Invoice-level billing, costs by department, and operational records – orders, shipments, returns, sales visits. Perfect data is not a prerequisite: mapping the gaps is part of the three-week diagnostic.
Want to see your portfolio’s whale curve?
Start with the free Profit Check – or book a scoping call directly.