My Business Depends on One Big Customer: How to Break Free
A three-line email wiped out more than half of a factory's revenue in one morning. How to get out from under a big customer before your email arrives.
Luiz Philipe (LP)
Updated October 24, 2026
It arrived at 7:12 on a Monday morning, signed by a procurement director Walt had never met. The old one, the man he had lunch with every year-end, had left the company in January.
Three lines. Sixty percent of the revenue of the corrugated box plant Walt had spent eleven years building.
He read it in the car, still in the parking lot, and turned off the engine. Inside, forty-some people were starting their shift, almost all of them working, without knowing it, for a single customer.
How a Company Gets to This Point
Nobody decides to depend on one customer. It happens gradually, and almost always for the best of reasons.
The big customer showed up early, paid on time and placed predictable orders. Every year they ordered more, and Walt bought a new machine to keep up. Prospecting seemed like a waste of time: why chase small orders when the big one kept the line full?
The salesman hired at the start became the person responsible for serving that account. Nobody else went out to sell. The company had one acquisition channel, just one, and that channel had a name, a last name and the title of procurement director.
This is the kind of risk that doesn't show up on the balance sheet. Revenue grows, profit appears, the plant looks solid. Until the day the person on the other side changes.
The Direct Answer
To get out from under a big customer, a company needs to open new acquisition channels while it still has the customer, not after the customer leaves. The safest path is to pick a small group of companies similar to your current customer, approach them in a planned way and add channels like trade shows, industry associations and partnerships with others who sell to the same audience. The goal isn't to lose the big customer; it's to reach a point where losing them hurts, but doesn't shut the company down.
The Call to Alice
On Tuesday, Walt called Alice.
They had met in a course years earlier. She owned a printing company that made industrial labels and, he vaguely remembered, had been through something similar.
I did, she said. About six years ago. A pharmacy chain. They were half my production. It was an email too, four lines. And how did you get out? I didn't, not that year. That year I laid people off, sold a machine and nearly closed. She paused. I got out afterward. And I promised myself that no customer would ever again be more than a fifth of what I bill.Walt asked how, in practice. He wrote down the answer on the back of an invoice, right there in the car.
First: your big customer is your best proof. They stayed with you eleven years. That's the most valuable thing you have to show any other buyer. Second: don't go out selling to everybody. Make a list of twenty companies similar to them and treat each one as if it were the only one. Third: go where the buyers in your industry meet. And fourth, the most important: you're going to do this forever, even after you have customers again. Prospecting isn't what you do when you're desperate. It's a routine of the company, like running payroll.The Plan That Came Off the Back of an Invoice
What Alice described has well-known names. Together, they diversify the book of business without losing focus on the kind of customer the company already knows how to serve.
1. Account-based marketing. Instead of talking to the whole market, the company picks a short list of target companies and builds a specific approach for each: who decides inside, what problem they have, what similar case you've already solved. First step: list twenty companies with the same profile as your big customer and find out the name of the buyer at each.
2. Customer stories. One well-told case, with the customer's permission, opens doors no presentation can. First step: write one page on what you delivered to your biggest customer and for how long. If you don't have permission to use their name, cite only the industry.
3. LinkedIn outreach and cold email. Approaching people you've never spoken to, with research and a short message that shows you understand their problem. First step: five personalized approaches a week, not fifty identical ones.
4. Industry trade shows. The buyers in your market gather in a few places, and the trade show is one of them. First step: pick one show, book the meetings before you go and plan the follow-up. There's a step-by-step in are trade shows worth it?.
5. Associations and chambers of commerce. Industry bodies bring together the people who buy and the people who refer. First step: attend one meeting as a listener and walk out with three contacts.
6. Partnerships with others who sell to the same customer. A printer, a freight carrier or a label supplier serves the same buyer you do. First step: propose a 30-day cross-referral arrangement to one of them.
7. Resellers and distributors. Someone who already has a customer base can carry your product to customers you can't reach alone. First step: talk to a regional distributor and learn what they would need to add your line.
None of these channels replaces the big customer in a month. Together, tested consistently, they change the shape of your book in a few quarters.
How to Tell If You're at Risk
A simple test: list your customers from the past year and how much each one represented in revenue. If a single one accounts for a slice that, on its own, would leave the company unable to pay its bills, you're already where Walt was in that parking lot. The difference is that you haven't received the email yet.
There is a kind of business owner who looks at their biggest customer and thinks: how lucky I am.
And there is another who looks at the same customer and thinks: I need more like them, before they leave.
Both serve well. Only one of them sleeps soundly when the procurement director changes jobs.
What Happened to Walt
Walt didn't save that quarter. He was honest with his team, renegotiated with the bank and cut a shift. It hurt.
But on Thursday of that same week, he made the list of twenty companies. The following Monday, he sent the first five messages. A year later, the plant's biggest account represented a slice that, if it left, would be a bad month. Not the end of eleven years.
Alice was right about one thing he only understood later: the problem was never the big customer. It was the plant having a single path to get customers. And the worst time to find out what the other paths are is the Tuesday after the email.
The 100 Acquisition Channels Guide, written by Luiz Philipe Campos, founder of Ímpetus Host, gathers 100 paths in 10 parts. In it you'll find account-based marketing, prospecting by email, LinkedIn and phone, trade shows, associations, distributors, government sales, partnerships and dozens of channels that people who depend on one customer almost never test. Each comes with what it is, a practical example, the first step to test it, who it works best for and what it costs to try. The spreadsheet that comes with the guide helps you score channels on cost, speed and fit and choose your first three. The 30-day, day-by-day plan helps you launch the first without dropping your operation.
Next step
Don't depend on a single way to win customers
Everything in this article works better when new customers arrive every month. Most businesses depend on two or three channels and suffer when one of them slows down. The 100 Acquisition Channels Guide shows 100 ways to win customers, a practical example of each one and the first step to test it spending little or nothing.
- ✓The 100 channels, one by one, from the best known to the ones almost nobody uses
- ✓A practical example and a low-cost first step for each channel
- ✓A simple way to choose the channels that fit your business now
- ✓Bonus: Channel scorecard
- ✓Bonus: 30-day test plan
One-time payment · Instant access · 7-day guarantee
Access is immediate, as a PDF, in your inbox. Read it before your next meeting with your biggest customer. If it doesn't work for you, Hotmart guarantees a refund within 7 days.
It costs less than a day of idle production. And it may be the cheapest thing you do this year to protect the other eleven.
Walt and Alice are characters created for this text.Frequently asked questions
What is the risk of depending on a single customer?+
When a single customer accounts for a large share of revenue, any change on their side, such as a new buyer, cost cutting or supplier consolidation, can threaten the entire company. On top of that, the big customer gains the power to push on price and payment terms. Diversifying your customer base reduces this risk without requiring you to lose the current customer.
How do I diversify my customer base?+
Start with companies similar to your best customer, because you already know how to serve them. Use account-based marketing, customer stories, active prospecting, trade shows and industry associations. Test one channel at a time, with a routine of at least 30 days, and add the next one after you measure.
What is account-based marketing?+
Account-based marketing is a B2B selling approach in which a company picks a short list of target companies and builds a specific approach for each one, instead of talking to the whole market. It works well for those who sell high-ticket offers and have few possible buyers. The first step is to build the list and find out who makes the buying decision at each company.
Where do I find acquisition channels for businesses that sell to other businesses?+
The 100 Acquisition Channels Guide has an entire part on active prospecting and direct sales, another on partnerships and another on communities and events, with channels like account-based marketing, trade shows, associations, distributors and government contracts. Each channel comes with a first step and a cost to test, and the guide includes a spreadsheet to choose your first three.
Does it work for my type of business?+
Yes. The channels cover local businesses, service providers, online stores, B2B companies and professionals. The guide helps you pick the ones that fit your case.
How do I receive the guide?+
Right after payment, Hotmart sends the access to your email. You can read it on your phone, computer or print it.
What if I don't like it?+
You have a 7-day guarantee. If it isn't for you, ask for a refund through Hotmart within that period.
The 100 Acquisition Channels Guide
100 ways to win customers without depending on a single source of sales
Get the 100 acquisition channels guide for $49One-time payment · Instant access · 7-day guarantee