A quiet truth sits beneath a lot of small and mid-market acquisitions in London, Ontario: revenue looks healthy, margins look decent, the seller seems trustworthy, yet one customer can make or break the whole story. If you plan to buy a business in London, your first serious diligence task is to find out how much of the company’s sales flow from a handful of names. Get this wrong and your beautiful model will crumble sometime between closing day and your first QBR.
Customer concentration is not a theoretical hazard. In my work around Southwestern Ontario, I’ve seen a manufacturing shop that got 68 percent of its top line from a single Tier 1 auto supplier. That supplier switched programs, the owner lost their primary contract, and the business had to cut half its staff within nine months. I’ve also seen concentration wielded as a moat. A specialized lab services company with two very sticky hospital clients had concentration above 70 percent, but the relationships were embedded, contracts were multiyear with automatic CPI escalators, and switching costs were brutal for the buyer. That deal worked out, because the risk was understood, priced, and insured.
Not all concentration is created equal, and not all deals in London, Ontario account for that nuance. The label “high risk” or “low risk” depends on who the customers are, why they buy, how long they’ve bought, and what would make them leave.
Why concentration bites harder in London, Ontario
London is not Toronto, and that’s a feature, not a bug. You get steadier labor markets, friendlier landlords, and better industrial space pricing. But you also get ecosystems where a single anchor employer or institutional buyer sets the tempo for dozens of suppliers. In London, government, healthcare, education, and a handful of manufacturers cast a long shadow. When you’re dealing with one major hospital network, one university, or one Tier 1 auto supplier as your top customer, their strategic decisions ripple into your P&L.
Local buyers sometimes lull themselves into thinking geographic proximity equals safety. “We know the decision makers, we sponsor their charity golf tournament, we’ve delivered to them for 20 years.” Longevity helps, but it doesn’t immunize you against budget freezes, procurement centralization, or a competitor moving in with a sharper price and faster lead times. Sometimes a new CFO at your customer can vaporize an entire product line with a spreadsheet and a mandate.
If you’re thumbing through listings for a business for sale London, Ontario on a Sunday afternoon, the teaser might not mention concentration. The CIM will hint at customer names without disclosing too much. The risk appears only when you see invoices, AR aging, and contract files during diligence. At that point, the temptation is to keep marching toward close because you’ve invested time and fees. Don’t. Slow down and break the risk apart.
How I define and measure concentration, beyond the 80/20 cliché
The classic metric is percent of revenue from the top customer, top three, and top five. Those numbers are a start, but they often mislead. A business with 30 percent exposure to a single customer can be safer than one with 15 percent if the first has long-term contracts with termination fees and the second has monthly purchase orders that are at-will.
I use a matrix that weighs five elements: revenue share, contract structure, switching costs, relationship depth, and customer health. The output isn’t a magic score, just a way to argue with myself.
- Revenue share. The raw percent of trailing twelve months sales tied to each major account, and the trend over three years. Growing concentration can be more dangerous than a static number. Contract structure. Length, renewal mechanics, termination rights, take-or-pay clauses, pricing review windows, and CPI or FX adjustments. A one-year auto-renew with 60-day termination is not the same as a five-year term with termination for cause only. Switching costs. Training, integration, regulatory approvals, unique tooling, or data migration hurdles that your customer faces if they leave you. The stronger the cost to switch, the safer the concentration. Relationship depth. How many nodes of contact exist? If the relationship lives in one sales rep’s phone, that’s fragile. If engineering, operations, finance, and executive sponsors talk across both firms, the web is stronger. Customer health. Your customer’s financial stability, strategic direction, and recent procurement behavior. A healthy company consolidating vendors could still cut you; a struggling firm might squeeze your margins even if they stay.
Score these qualitatively, then look for contradictions. If the top customer is 45 percent of revenue, but you have a multiyear MSA with minimums, quarterly business reviews with three functional leaders, and custom tooling on your floor that they paid for, the risk is real but containable. If the top customer is 20 percent, but orders are ad hoc, the buyer has a new head of procurement, and there’s a cheaper substitute, I’d treat that as a tripwire.
Anecdotes from the field
A local packaging company in the London area relied on a single food processor for 52 percent of its revenue. The seller insisted the relationship was “like family.” On diligence, we discovered the customer had announced a plant consolidation to a site two hours away, with a new ERP and a different packaging spec. Nobody had told the seller. As soon as we learned that, the model changed. We renegotiated price, added an earnout, and secured a side letter from the customer that clarified transition volumes. The deal closed, the volumes dipped 25 percent for a year, then recovered. Without that adjustment, the buyer would have overpaid and possibly breached covenants.
Another time, a business broker London Ontario introduced a digital services firm with two top clients in the public sector. Concentration looked terrible on paper, but both clients required enhanced security clearances and had bespoke integrations that would cost six figures to replicate. The contracts renewed every two years, but renewal success was 100 percent across four cycles. We still pushed for a holdback tied to renewal, not out of fear, but discipline.
These small stories matter because customer concentration is rarely a single number problem. It is a narrative about why your customer buys and what would make them stop.
What a seller’s narrative reveals
When a seller waves off concentration concerns, listen closely to the verbs they choose. “They always,” “they never,” “they wouldn’t do that to us,” “we’ve known them forever.” That language hides risk. Good sellers talk in specifics. They’ll show contract renewal calendars, explain price adjustment mechanisms, and introduce you to three people at the customer who can articulate why your company is critical to them.
If you’re reviewing a business for sale London, Ontario and the seller resists customer interviews or delays providing contract files, treat it as information. Sometimes the resistance comes from genuine confidentiality obligations, especially with healthcare or defense-adjacent accounts. Often, though, it signals that the story is fragile. In those cases, insist on a structured path: anonymized summaries first, then redacted agreements, then controlled customer calls under a non-solicitation framework.
Pricing the risk, not just spotting it
If concentration is real and cannot be mitigated pre-close, price it. This tends to be where deals go sideways because buyers want a massive discount and sellers want their headline number. The middle ground involves alignment on what happens if the big customer leaves or shrinks.
There are four practical levers. Adjust the base price down to reflect expected value at risk. Create an earnout tied to revenue or gross profit from the top accounts. Hold back a portion of the purchase price in escrow, released upon meeting retention milestones. Or use representation and warranty insurance with a specific customer non-termination bring-down, though that tends to be expensive and narrow in smaller deals.
For service businesses with under 5 million in EBITDA, I usually push toward an earnout plus a targeted holdback. It protects the buyer without starving the seller, and it rewards both parties for a calm hand-off. A typical structure might hold back 10 to 20 percent and release it in tranches after 12 and 24 months if the top customers remain above a threshold.
Operational moves that reduce concentration after closing
Buyers often wait until they own the company to invest in diversification. That’s fine if you’ve already priced the risk. Still, even before close you can sketch a ninety-day plan focused on strengthening what you have and widening the funnel.
- Meet the customer’s operators, not just purchasers. Sit with their plant manager, their IT lead, or their clinic administrator. Learn what annoys them and fix it quickly. Reliability trumps charm. Lock in talent. If two staff members hold the relationship glue, put retention bonuses in place and clarify their path. A nervous account manager can tank a handover. Create micro-wedges inside the account. Add small adjacent services that make you harder to replace, like inventory forecasting or on-site kitting for a manufacturer, or compliance documentation support for a hospital. Improve lead response and quoting. Concentrated businesses often neglect new customers because the big account keeps them busy. Fix intake, quoting speed, and onboarding. Build a short list of two or three target customers with the same profile as your anchor. Even one small win lowers risk and changes lender sentiment.
These moves seem simple, but I’ve watched them shift a business from “one-customer shop” to “reliable niche provider” in a year.
Banking and lender sensibilities in Southwestern Ontario
Local lenders in London are pragmatic. They understand the landscape, but they will view concentration through the lens of loan recovery. If top customer exposure is above 35 percent, expect more conservative leverage, tighter covenants, and a bigger cash reserve ask. If exposure pushes above 50 percent, you may need mezzanine or vendor take-back to close the capital stack.
What helps in credit committee? Clear contract documentation, customer attestations or letters of intent, and a written post-close plan for diversification. A line of sight to gross margin stability matters as much as revenue. If the top customer represents 45 percent of sales but 60 percent of gross profit due to scale efficiencies, you have to show what happens to contribution margin if they renegotiate.
I’ve had lenders change their mind after one ten-minute customer call where the buyer asked the right Learn more questions about integration roadmaps and volume forecasts. The inverse is also true. A vague answer from the customer about “reviewing preferred vendors” can push a bank to cut a turn of leverage at the last minute.
Sector-specific wrinkles buyers often miss
Some patterns repeat in London and nearby markets.
Healthcare and education. Budgets may be annual, but relationships can last decades. Procurement cycles are formal, and losing a public tender early in your hold can wipe out your biggest account. If you see concentration in this space, watch for framework agreements and preferred vendor lists. The smartest move is to get the procurement cycle calendar and note when the next retender hits.
Auto and advanced manufacturing. Program lifecycles matter more than contract length. A purchase order may run for years, but the program can end abruptly with a model change. Ask for the customer’s program timeline and where the business sits in it. Tooling ownership is critical. If the customer owns the tooling sitting on your floor, your bargaining power drops.
Software and IT services. MRR concentration can be deceptively high in a 2 to 4 million ARR shop. Pay attention to logo churn versus dollar churn, the distribution of admin users inside the customer, and integration depth. If your product or service is embedded in workflows, your risk might be lower than the raw number suggests.
Construction and trades. Projects define the revenue. A single GC might represent 40 percent in one year and 10 percent the next. You need a three-year view and a backlog analysis. Concentration that swings wildly can be fine if the underlying pipeline is broad.
These nuances often decide whether a buyer should walk or push forward with modifications.
Working with a broker without outsourcing your judgment
A seasoned business broker London Ontario can help you surface concentration early, but they work for the seller unless you have a buy-side engagement. Brokers vary in how they present the risk. Some will highlight it with context. Others will downplay it. Treat their decks as an index, not a verdict. Ask brokers for anonymized revenue by customer and then for retention history. A fair broker will get you what you need, even if it takes a staged disclosure.
If you’re scanning listings for a business for sale London Ontario and you see phrases like “diversified customer base” without a chart, request the chart. Ask for a simple Pareto: top ten customers, revenue share, and tenure. Also ask for the top five lost customers in the last three years and why they left. Lost-customer reasons reveal more truth than current-customer praise.
Negotiation posture that keeps relationships intact
Customers hate surprises. If they find out about an ownership change in the legal notice, you’re starting on your back foot. Coordinate with the seller on a customer communication plan that respects the customer’s culture. Some prefer a quick formal note and a call. Others want a joint visit with the seller and the buyer present. The goal is to reassure on continuity, then add value with your plan for better service or broader capabilities.
If concentration is high and you need a consent or novation, get ahead of it. Map the legal steps and the procurement steps. In public sector, a consent might trigger an assignment review. In private sector, it can be as simple as an email, but someone in legal will still want to check boxes. Build time for it.
When to walk away
There are times to close the folder and move on, even in a tight market with few quality opportunities.
If the top customer refuses a basic reference call or blocks consent unreasonably, your downside is too big. If the seller won’t budge on price or structure despite evidence of elevated risk, you’ll end up paying for their history, not your future. And if concentration sits on top of other fragilities, like expiring key-man insurance, deferred maintenance, or shaky financial controls, you’re stacking risks with correlated failure modes.
Passing on a deal teaches discipline. There will be another business. London’s market is not as deep as Toronto’s, but quality companies come to market every quarter, and some of the best never hit the open listings.
How to prepare if you’re the seller
Sellers in London, Ontario often shrug at concentration because it paid the bills for years. If you plan to exit in the next 12 to 24 months, do three things.
Tighten contracts. Even modest improvements help: add auto-renew, specify notice periods, insert CPI-based pricing adjustments, and clarify ownership of tooling or IP. Buyers will pay for certainty.
Spread the relationship. Introduce second-layer managers across both companies. Document workflows. Move institutional knowledge out of heads and into shared systems.
Show a path to diversification, even if early. A few new logos or small pilots with credible prospects can change the negotiation tone. Buyers do not need a miracle, they need evidence of motion.
With this groundwork, your eventual buyer will be more confident, your banker more supportive, and your exit multiple more defensible.
A buyer’s field checklist for concentration
Use this in the data room and in your early calls.
- Obtain a customer-level revenue breakdown for three years, with gross margin per account if available. Review top customer contracts: term, renewal, termination, pricing adjustments, and any change-of-control clauses. Interview at least two operational stakeholders at the top customer, not only procurement or sales contacts. Map switching costs: integrations, certifications, tooling, and process dependencies. Align price and structure with the risk: earnout mechanics, holdback triggers, and covenant buffers.
Keep this list small and focused. The point is to identify whether you’re buying a platform with a strong anchor or a single-peg stool.
The London, Ontario angle for buyers from outside the region
If you’re coming from Toronto, Kitchener-Waterloo, or across the border, remember that relationships in London move at a human cadence. People pick up the phone. A sincere site visit beats a slick deck. The city’s economy mixes white-collar institutions and hardworking industrial shops. Customer concentration often mirrors that: one hospital or one OEM as the anchor. That can be an asset if you respect the relationship and invest in depth rather than try to “optimize” it on day one.
Local suppliers care about service quality more than flash. If you buy a business in London, prove you can keep promises through winter storms and inventory shortages. When vendors see that, they’ll introduce you to their other customers. That, more than any marketing campaign, reduces concentration risk.
Final thoughts that matter when the papers are on the table
The hard part of concentration is accepting that it isn’t purely a math problem. It is a story about fit, friction, and habit. Customers keep buying from the same vendor because it saves them time, covers their risk, and fits their internal politics. Your job as a buyer is to understand that web and decide whether you can maintain it and gradually weave a few more threads.
If you get the analysis right, you’ll be comfortable walking into deals that scare others, especially those browsing for a business for sale London, Ontario and passing at the first mention of a 40 percent customer. You’ll know when that 40 percent is actually safer than a scattered set of tiny accounts with high churn and low loyalty. And when the risk is real, you’ll know how to price it, structure it, and actively manage it the minute you take the keys.
The sunset metaphor in dealmaking gets used a lot. To me, Liquid Sunset Focus 2.0 means watching the light as it changes, not looking away at the flash. Concentration is bright and obvious, but if you watch closely, you’ll see the contours beneath it: contracts, people, processes, and switching costs. That’s where deals are won, where lenders nod, and where a London, Ontario acquisition becomes a compounding asset instead of a cautionary tale.