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// WORKED EXAMPLEWHERE THE RISK SITS

Supplier Concentration: Where the Credit Risk Sits

Lend to the dealer, and you have lent against the dealership.

BY MICHAEL SHANG · SIXTEEN YEARS IN COMMERCIAL BANKING · UPDATED

// THE SHORT ANSWER

Supplier concentration matters to a lender because a business that cannot buy cannot sell. When one supplier provides most of what a borrower trades, that supplier's decisions reach the bank's cash flow and its security: it can end the agreement, tighten payment terms, raise prices or claim back stock it has not been paid for. A lender's reading therefore asks how long the borrower could trade without that supplier, what the supply agreement lets the supplier do and on what notice, and how much of the stock in the borrowing base still belongs to the supplier.

BASIS  Practitioner judgment from sixteen years in commercial banking, set out in How Bankers Think (Highbank Press, 2026). Every borrower on this site is a composite constructed for teaching, not a client. The market is mid-market commercial lending as practised in New Zealand and Australia; where a convention differs elsewhere, the page says so.

// MAKE THE CALL

Issue 10 — The Dissent. The paper recommends approval. You found the hole. You're the third vote of five — and the RM outranks you. Your call first, then the senior banker's.

Read the file →

// 01 — WHY ONE SUPPLIER BECOMES THE BANK'S RISK

A lender is used to asking who pays the borrower. It asks less often who the borrower depends on, and the answer can matter as much. A dealer holding one manufacturer's franchise, a processor with one source of a raw material, a software reseller whose product is licensed from one owner: each has revenue that exists because another business keeps supplying it. If that business stops, the revenue stops with it, however loyal the customers are.

Dependence alone is not the risk. Plenty of businesses buy most of their inputs from one supplier because it is the best, and could switch in a month if they had to. The risk is dependence that cannot be undone quickly: an exclusive range customers ask for by name, an input with long qualification times, a licence with no substitute. That is the case where the supplier's choices, not the borrower's, decide what the business earns next year.

// 02 — HOW A LENDER MEASURES IT

The first number is share: purchases from the largest supplier as a share of total purchases, and the revenue and gross margin that depend on those purchases. The second is time: how long the borrower could keep trading if supply stopped, which depends on stock on hand, the notice the agreement gives and how long a replacement would take to arrange. The third is terms, because a supplier does not have to leave to hurt the business. It can shorten the credit it gives, which turns into a working capital need overnight.

Supplier credit = annual purchases from the supplier × days of credit ÷ 365
Cash released or absorbed = change in supplier credit when the terms change

The fourth is title. Suppliers commonly sell on retention of title terms, keeping ownership until they are paid. In New Zealand and Australia such a term is a security interest under personal property securities law, and a supplier that registers it on the PPSR in time can rank ahead of the bank's general security over the goods it supplied. In the UK a simple retention of title clause is not a registrable charge, so the register will not show it; the lender learns of it from the supply terms.

// 03 — THE EXAMPLE

A forklift dealer, constructed for this page like every figure in it, is the regional distributor for one overseas manufacturer. Of its US$32m of revenue, 74% is that brand's trucks and parts, 16% is workshop labour on any make and 10% other ranges. The distribution agreement renews each year and either side can end it on six months' notice. The dealer buys US$20m a year from the manufacturer on 90 days' credit, and its bank lends against stock at an advance rate of 50%, the example's rate rather than a market norm.

Stock in the borrowing base 7.2m
Stock supplied by the brand, title retained − 5.0m
Stock the bank can rely on 2.2m
Availability as the dealer reports it: 7.2 × 50% = 3.6m
Availability with title checked: 2.2 × 50% = 1.1m

The manufacturer's retention of title, registered on the PPSR, covers its stock until it is paid, so more than two-thirds of the stock line was the supplier's security before it was the bank's. Then the terms:

Supplier credit at 90 days: 20 × 90 ÷ 365 = 4.93m
Supplier credit at 30 days: 20 × 30 ÷ 365 = 1.64m
Cash the dealer must find 3.29m

If the manufacturer cuts its credit to 30 days, perhaps because its own credit insurer has trimmed the dealer's limit, the dealer needs US$3.29m within a quarter, three times what its stock line will now lend. And if the manufacturer gives notice, the dealer has six months to replace three-quarters of its revenue. The workshop revenue survives; the rest depends on whether another brand will appoint it.

// 04 — HOW IT DIFFERS FROM CUSTOMER CONCENTRATION

The two are read together because both make one outside party decisive, but they fail differently. A lost customer, the risk behind customer concentration, takes revenue with it and leaves the business free to sell to someone else. A lost supplier can leave the business with its customers and nothing to sell them. The lender's remedies differ. Against a customer the bank watches the debtor ledger and the buyer's credit. Against a supplier it reads the supply agreement, the supplier's own health and the supplier's claim on stock.

The two can also meet. A business that sells most of its output to one buyer and sources most of its input from one seller has its margin set at both ends by others. That is the reading behind a take-or-pay contract seen from the other side, and behind many files in How Banks Read Retailers.

DEFINED IN ONE PARAGRAPH → · RETENTION OF TITLE → · THE BORROWING BASE CERTIFICATE →

// 05 — WHERE IT DECIDES A FILE

It decides the security first. A lender that counts stock without checking whose it is lends against goods another creditor can take, so supplier-financed stock is commonly excluded from a borrowing base or advanced against only after the supplier is paid. It decides the facility next. A loan whose tenor runs well past the supply agreement's notice period is a loan that outlives its revenue, so the bank may ask for the agreement to be renewed on longer terms, for notice to be reported to it as soon as it is given, or for a working capital line with room for a change in terms.

Statute helps less than borrowers expect. In the UK, and in Australia for contracts made since July 2018, the law stops many suppliers from ending a supply contract merely because the customer has entered certain formal insolvency processes. Those protections do not oblige a supplier to renew an agreement that expires, and they do nothing for a borrower that is still trading when the notice arrives.

// SOURCES

The documents the statements on this page rest on. Each was opened and checked when cited.

  1. UK Insolvency Act 1986, section 233B (inserted by the Corporate Insolvency and Governance Act 2020) — subsections (2) to (4) — A provision letting a supplier terminate a contract for the supply of goods or services because the customer has entered a listed insolvency procedure ceases to have effect — section 05.

// QUESTIONS PEOPLE ASK

What is supplier concentration risk?
It is the risk that a business depends on one or a few suppliers it cannot replace quickly, so that a supplier's failure, price rise, change in payment terms or decision to stop supplying damages the business. It is measured by the share of purchases or revenue tied to the largest suppliers, by how long the business could trade without them, and by what the supply contracts allow each side to do.
How do you reduce supplier concentration?
By qualifying a second source for key inputs, holding more stock of items with long lead times, negotiating longer notice and renewal terms in the supply agreement, and building revenue that does not depend on the main supplier, such as service work across several brands. Each costs money, and a lender reading the file weighs whether the borrower has spent it or is relying on the relationship holding.
Does retention of title beat a bank's security?
It can. In New Zealand and Australia a retention of title term is a security interest, and a supplier that registers it on the PPSR in time can rank ahead of a bank's general security over the goods it supplied, even if the bank registered first. If it does not register, it can lose to a perfected security interest, and in Australia an unperfected interest generally vests in the company if it goes into administration or liquidation. In the UK a simple retention of title clause needs no registration, so a lender reads the supply terms.
Is a business that buys from one supplier a bad credit risk?
Not of itself. Many sound businesses buy most of their range from one manufacturer under a long relationship. The risk depends on how replaceable the supplier is, how much notice it must give, what terms it trades on and whether its stock in the business is paid for. A lender that has read those can lend with conditions; one that has not is lending against an agreement it has not seen.

THE IN-TRAY · ONE MINUTE

Make the call on one file.

A short file on the ground this page covers. Every option opens with how far it sits from a senior banker’s read.

THE CALL · CHAPTER 1

A five-year loan to a single-site manufacturer. No financial covenants. Security is specialised plant that only a handful of buyers could use. The credit is strong today.

Which question has the file left open?

1 FILES · PICK A CALL ON ANY OF THEM

5 MORE ON CHAPTER 1 · THE THREE QUESTIONS →WHERE DO YOU READ FROM? THE PLACEMENT →