Customer concentration reduces what you can borrow in two ways. Cash-flow lenders lend at lower leverage and want more coverage cushion when one customer carries a large share of profit, because losing it would hit debt service directly. Asset-based lenders cap each customer's share of the borrowing base, commonly at 20% to 25% of eligible receivables, so invoices above the cap earn no availability. Lenders may also add reporting and covenants. Long contracts, long tenure and a creditworthy customer ease the concern, and a file that shows the concentration openly is treated better than one where the lender finds it.
- Cash-flow loans
- Lower leverage, more cushion over the coverage test, sometimes shorter amortization
- Asset-based lines
- Single-customer caps, commonly 20% to 25% of eligible receivables
- Factoring and contract finance
- The customer's credit is underwritten directly
- What eases it
- Contract term, tenure, the customer's credit quality, switching costs
- What lenders may add
- Customer reporting, notice of a key customer's loss, tighter covenants
Where lenders start to react
There is no single percentage of revenue at which every cash-flow lender becomes cautious. Questions start when the largest customer is a meaningful share of the business and grow sharper as that share rises. Lenders look past revenue to gross profit, because a large, thin-margin account matters less to debt service than its sales suggest, and they look at the top five and top ten together, because several mid-sized customers can be as fragile as one big one.
They also look for concentration that does not appear on a customer list: one distributor that reaches many end buyers, one platform that carries most online sales, one government program that pays for most patients, one general contractor behind most jobs. To a lender, a single decision-maker who can cut off most of your revenue is a single customer, however the invoices are addressed.
How concentration is handled depends first on the kind of loan, because each kind of lender is exposed to the customer in a different way:
| Type of financing | How the lender is exposed to the customer | How concentration shows up |
|---|---|---|
| Term loan (bank, private credit, SBA) | The customer's profit pays the debt | Lower leverage, more coverage cushion, closer reading of the contract |
| Asset-based line of credit | The customer's invoices are the collateral | Single-customer caps in the borrowing base; the customer's payment record matters |
| Factoring | The factor is repaid by the customer directly | Credit limits per customer; a strong customer can make concentration acceptable |
| Contract or purchase-order finance | The customer's order is the reason for the advance | The customer's credit and the contract terms are the underwriting |
Borrowing-base limits, worked through
Asset-based lenders deal with concentration mechanically. Borrowing bases commonly cap any single customer at 20% to 25% of eligible receivables, and asset-based lenders typically advance 80% to 90% of eligible receivables. Receivables more than 90 days past invoice are typically ineligible anyway.
An example in plain numbers. A company has eligible receivables of 1,000, of which one customer owes 450. With a single-customer cap at 25%, only 250 of that customer's balance counts; the other 200 is excluded. Eligible receivables fall to 800, and at an advance rate of 80% the company can draw 640. Without the cap it could draw 800. Nothing about the customer changed; the line is simply smaller because the collateral is less diversified.
Two refinements matter. Many lenders apply cross-aging: if enough of one customer's balance is past due, they exclude the whole of it, which hits hardest when that customer is also the largest. On the other side, lenders often allow a higher cap for a customer with strong credit, and some give more room when the receivables are credit-insured. Concentration limits and eligible versus ineligible receivables cover the mechanics, and how a borrowing base works puts them in context.
On a line of credit, concentration is not a judgement call. It is a formula, and you can calculate its effect before you apply.
How concentration haircuts a cash-flow loan
Senior cash-flow lenders to lower-middle-market companies commonly lend 2x to 3.5x EBITDA, and conventional bank lenders commonly look for debt service coverage of at least 1.25x. A concentrated business tends to land toward the lower end of the leverage range, and lenders want coverage comfortably above the minimum rather than just at it. The haircut is not arbitrary: the lender is asking how much of its loan depends on one relationship continuing.
The contract term often shapes the structure as much as the amount. If the largest customer's contract runs for three more years and the loan runs for seven, a lender may prefer faster amortization in the early years, so that by the time the contract comes up for renewal the remaining debt is something the business could carry without that customer. In plain numbers: a company borrowing 3,000 whose business without its top customer could support about 1,500 of debt might be asked to amortize enough over the contract's remaining term to bring the balance close to 1,500 by renewal.
The same logic applies to SBA loans. SBA sets no concentration rule of its own, but SBA lenders apply their own judgement to the historical cash flow that must cover payments at least 1.15x, and they ask the same questions about who pays it. How much debt a business can carry shows the leverage and coverage tests the haircut is applied to.
Covenants and reporting a lender may add
When the mitigants only partly answer the concern, lenders often lend anyway and keep a closer watch. Common additions:
- Customer reporting. Sales and receivables by customer with each compliance report, so the lender sees a decline early.
- Notice of a key customer's loss. An obligation to tell the lender if the largest customer terminates, gives notice or materially reduces orders. Some agreements treat that event as grounds to renegotiate; others rely on the general material adverse change clause.
- Tighter financial covenants. A coverage or leverage covenant set with less headroom, so trouble shows up as a covenant conversation before it becomes a missed payment. See covenant headroom.
- Limits on distributions. Cash stays in the business until the concentration falls or the loan pays down; see distributions under a loan.
- A cash sweep. Part of excess cash flow goes to prepay the loan, which speeds up the deleveraging described above; see excess cash flow sweeps.
On an asset-based line, the lender may also watch the key customer's payment pattern through the borrowing base certificate and add a reserve if it slows. Line of credit covenants covers how these clauses are usually written.
What eases the concern
| Mitigant | Why it helps | What proves it |
|---|---|---|
| Contract term | Revenue is committed for a known period, ideally beyond much of the loan's repayment | The signed contract, with renewal and termination terms |
| Tenure | A relationship that has survived price increases and bad years is less likely to end suddenly | Several years of sales by customer |
| The customer's credit quality | A large, creditworthy customer that pays on time is a different risk from a small, slow payer | AR aging by customer, with days outstanding |
| Switching costs | A product specified into the customer's process, or certifications the customer needs, is hard to replace | Specifications, approved-vendor status, qualification history |
| Breadth inside the customer | Selling to several divisions or sites spreads the decision across several buyers | Sales by customer location or division |
| Diversification trend | Concentration falling year by year is read very differently from concentration rising | The multi-year customer report, with new accounts identified |
None of these removes the risk. They change the lender's estimate of how likely the loss is and how much warning there would be. A long contract with a creditworthy customer, a decade of history and a falling share of revenue can support leverage close to what a diversified business would get. A purchase-order relationship with no contract, with one buyer, and a rising share cannot, however long it has lasted.
Presenting concentration honestly in the lender package
Concentration is better disclosed than discovered. A lender who finds it in the AR aging after reading a summary that did not mention it starts to wonder what else the summary left out. A lender who reads it on the first page, with the evidence and the downside case beside it, starts from the mitigants.
A good file for a concentrated business includes:
- Revenue and gross profit by customer for two to three years, ranked, with the trend
- AR aging by customer, with days outstanding, and a customer list with the balance owed by each
- The contracts with the largest customers, with term, renewal, termination and change-of-control provisions
- A short account of each key relationship: how long it has run, who manages it, and how pricing is set
- A downside case in the financing model showing coverage and liquidity if the largest customer is lost or cuts orders
Transparent builds that downside case into the financing model and addresses concentration directly in the underwriting memo and lender presentation. The blind teaser describes the key customer by its type and standing, not its name, so lenders can judge the credit before they sign a confidentiality agreement. Once the documents are in, the full package is built in a day; the package shows what it contains. If the concentration arises in a purchase, customer concentration in an acquisition covers the extra issues a change of owner brings, and factoring versus asset-based lending compares the two receivables routes that treat a strong customer most favorably.
Common questions
- What share of revenue from one customer is too much for a lender?
- There is no single cut-off for cash-flow loans; the questions sharpen as the share rises and depend on the customer's credit, the contract and the trend. Asset-based lines are more mechanical: borrowing bases commonly cap any one customer at 20% to 25% of eligible receivables.
- Is factoring easier than a bank line for a concentrated business?
- Often, when the large customer has strong credit. A factor is repaid by the customer directly, so it underwrites that customer and sets a credit limit for it, rather than penalizing the concentration itself.
- Can I raise the concentration cap in my borrowing base?
- Sometimes. Lenders may allow a higher cap for a customer with strong credit, and some give more room when the receivables are credit-insured. The request is stronger with the customer's payment history in hand.
- Will a lender add a covenant tied to my biggest customer?
- Some do, usually a requirement to report sales by customer and to give notice if the key customer terminates or cuts orders. More often the protection comes from tighter general covenants and limits on distributions.
- Does SBA limit customer concentration?
- SBA has no concentration rule of its own. SBA lenders apply their own judgement to whether the historical cash flow covering the loan depends too heavily on one customer.
- Should I name my largest customer in the lender package?
- In the full package, yes, with the contract and payment history. In the blind teaser that goes to lenders first, the customer is described by type and standing without being named.