Single Source and Sole Source Justification for Equipment (Template)

A sole source purchase is one where only one supplier can provide the item at all. A single source purchase is one where alternatives exist, but one supplier is chosen for a documented reason, such as compatibility with installed equipment [1]. Both skip open competition, so both need a written justification that shows the alternatives were considered, why they were rejected, and that the price is fair.

Most published templates are US public sector forms. Industrial buyers need the same discipline for different reasons: auditors, finance teams and, at regulated sites, quality teams will ask why a purchase went to one supplier without competition.

Why this matters now

Two pressures pull in opposite directions. Supply risk pushes buyers towards more suppliers: in Deloitte's 2025 survey of chief procurement officers, 74% named finding alternative supply sources as the most effective way to reduce risk [2]. Meanwhile, the installed base, validated processes and OEM spares keep pushing purchases back to one supplier. The justification is where you show you weighed both.

The cost of weak justifications is well documented. The National Audit Office found that of £17.3 billion of new COVID related contracts, £10.5 billion was awarded directly without competition, and it found inadequate documentation in a number of cases [3].

Valid reasons in equipment buying

The UK's Procurement Act 2023 gives public buyers a useful checklist. Its direct award justifications include goods that only one supplier can provide because of intellectual property or other exclusive rights, or for technical reasons with no reasonable alternative; additional goods from the existing supplier where a change would cause incompatibility or disproportionate technical difficulties in operation or maintenance; and extreme and unavoidable urgency that the buyer did not cause and could not foresee [4]. Private buyers are not bound by the Act, but the same reasons hold up well:

On validated equipment, ICH Q10 expects changes to be assessed with quality risk management so there are no unintended consequences [5]. Staying with the original supplier can be the right answer, but write down why switching would cost more than the competition would save.

Weak reasons include "we always use them", "they are cheapest" without a price check, and urgency caused by late planning. One university procurement guide makes the same points: an existing relationship or incumbency cannot on its own justify a non competitive award, and urgency is measured from when the need arose [6].

Template

Keep the market check honest. A short search for alternatives, recorded with dates and results, is the part auditors look for first. Our guide on how to find and vet suppliers covers the search itself.

The risk of not testing the market

Every single source decision creates a dependency. Prices drift up when a supplier knows it will not be tested, lead times stretch, and if the supplier fails, there is no qualified alternative. Set a review date on each justification, and use it to test the market again. Our article on vendor risk management covers how to track that dependency across a supplier base.

Practical example

In this illustrative example, a site needs two replacement mechanical seals for a qualified pump on a GMP line. Engineering confirms the seals are OEM designs, and quality notes that a different seal would need a change assessment and requalification of the pump. The buyer searches for licensed alternatives and finds one distributor of the same OEM seal, at a price 4% higher with a longer lead time.

The justification records single source to the OEM, attaches the engineering and quality notes and the search result, compares the price with the last two orders, and is approved by the procurement manager with a review date in 12 months. At the review, the buyer asks the OEM for a framework price and checks whether a qualified second source has emerged.

Where ChemCapital fits

Supplier Discovery makes the market check quick and recorded. You describe the need in plain text or upload a spec, and it searches the open web for suppliers, returning each with the web address where it was found, its published parameters and a fit verdict. Each search, brief and verdict is recorded with its source, which gives a single source justification the evidence that alternatives were looked for. You can try three searches free, with no sign up.

Ready to document your market checks properly? Start a free 14 day ChemCapital trial, with no credit card needed.