Sole Source Justification: What to Include, With an Example

A sole source justification is the written case for buying from one supplier without competition. Public agencies, grant-funded organizations and many companies with a purchasing policy generally require one before they approve a noncompetitive purchase. This guide covers what a strong justification contains, the reasons reviewers turn down, the US federal and grant rules, and an example outline.

What a sole source justification is

It’s a document explaining why a purchase should go to one named supplier without competing offers. In US federal buying it’s commonly called a justification and approval (J&A). It describes the need, shows why only this supplier can meet it, records the search for alternatives and explains why the price is reasonable.

Public and grant-funded buyers generally have to compete their purchases, and many company policies require competition above a set value. The justification records why this purchase is an exception.

Sole source vs single source

The usual distinction:

Usage varies, so check your own policy. Some organizations treat the terms as one, and the federal grant rules use “single source” for the only-one-supplier case (2 CFR 200.320(c)(2)). Supply chain teams also use “single sourcing” for a deliberate strategy of buying an item from one supplier. Where a policy separates the two, expect a single source purchase to need a written justification too, and to be harder to defend, because alternatives exist.

When sole sourcing is typically allowed

Your policy, or the law that governs your spending, lists the grounds. Common ones:

• Only one supplier can provide it, because of proprietary technology, exclusive rights or no authorized resellers.
• Compatibility, such as an add-on that has to work with an existing system.
• Follow-on work, where switching suppliers partway through would duplicate cost or cause unacceptable delay.
• A genuine emergency. Buy what the emergency requires and compete the rest.
• Failed competition, where you solicited several sources and didn’t get adequate competition.
• Low value, below the point at which your rules require competition.

Two cases look like sole source but usually aren’t. If one brand is required but several resellers sell it, compete on price with a request for quotation (RFQ), though you may need to justify the brand. And if one supplier simply seems strongest, that’s a competition you haven’t run: see the vendor selection guide.

What a strong justification contains

Reviewers look for facts they can check. Cover:

1. The need. What you’re buying, why, the scope, the term and the estimated value including renewals and options.
2. Why only this supplier can meet it. Specific facts with evidence attached, such as the module running only on the vendor’s platform.
3. Market research and who else you considered. When and how you looked (searches, calls, an RFI, a public notice of intent) and what you found. Name each alternative and say why it falls short.
4. Why competition isn’t practical. Connect the facts to the conclusion, such as having to replace a whole system to buy one module.
5. Price reasonableness. Show the price is fair without competing offers, for example against the supplier’s price list and discounts to similar customers, past prices, other public bodies’ contract prices or an independent estimate made before you saw the quote.
6. Approvals. The person who knows the need certifies the technical facts, procurement reviews the rest, and the approvers your policy names sign.

Also state how long the arrangement lasts and how you’ll allow competition next time, such as through the next RFP.

Weak reasons that get rejected

• Preference. “They’re the best” is a claim a competition would test.
• Familiarity. “We’ve always used them” isn’t uniqueness. If switching has real costs, estimate them.
• A deadline caused by poor planning. FAR 6.301(c) bars justifying a noncompetitive federal contract on a lack of advance planning or on funds about to expire. Any reviewer will ask whether the deadline was avoidable.
• A specification written around one product. Requirements copied from a brochure produce one compliant supplier by design.
• Proprietary rights alone. FAR 6.302-1(b)(2) says the mere existence of patent or data rights doesn’t in itself justify a sole source.
• The vendor’s sole source letter as the only evidence. It shows what the vendor says, not what the market offers.

The RFP process guide warns against running an RFP after you’ve already chosen. If only one supplier can meet the need, justify a sole source openly instead.

Federal, grant, state and private rules

US federal agencies: FAR Part 6

A federal contract awarded without full and open competition must fit an exception in FAR 6.302:

• 6.302-1 Only one responsible source and no other supplies or services will satisfy agency requirements
• 6.302-2 Unusual and compelling urgency
• 6.302-3 Industrial mobilization; engineering, developmental, or research capability; or expert services
• 6.302-4 International agreement
• 6.302-5 Authorized or required by statute
• 6.302-6 National security
• 6.302-7 Public interest

FAR 6.302-1 applies when the supplies or services “are available from only one responsible source” (for DoD, NASA and the Coast Guard, one or a limited number) “and no other type of supplies or services will satisfy agency requirements.”

FAR 6.303-2 sets the minimum content, including the authority cited, why the contractor’s unique qualifications or the nature of the acquisition requires it, efforts to solicit as many sources as practicable, the market research, the contracting officer’s determination that the cost will be fair and reasonable, and actions to remove barriers to future competition. The contracting officer certifies it as accurate and complete.

Under FAR 6.304, the approval level rises with the estimated value, including options: the contracting officer’s certification at the lowest level (unless agency procedures set a higher one), then the advocate for competition, the head of the procuring activity and, for the largest contracts, the senior procurement executive. FAR 6.305 requires public posting, generally within 14 days after award.

Part 6 doesn’t apply to simplified acquisition procedures (FAR 6.001(a)). For those purchases, FAR 13.106-1(b) covers soliciting a single source, and sole source purchases of commercial products and services under FAR subpart 13.5 still need a written, approved justification under FAR 13.501.

FAR references are to the text on acquisition.gov as of October 2026. The FAR is being rewritten under the Revolutionary FAR Overhaul, and agencies can apply deviations. Agencies using the overhauled Part 6 find these rules at FAR 6.103, 6.104-1, 6.104-2 and 6.301 (exceptions, content, approval and posting). Check the current text before relying on a section number.

Federal grant recipients: 2 CFR 200.320(c)

States, including their agencies and instrumentalities, and Indian Tribes spending federal award money follow their own procurement policies plus a few listed sections (2 CFR 200.317). For other recipients and subrecipients, such as nonprofits and local governments, 2 CFR 200.320(c) allows noncompetitive procurement only when:

• The purchase doesn’t exceed the micro-purchase threshold.
• It can only be fulfilled by a single source.
• A public exigency or emergency won’t permit the delay that public notice of a competitive solicitation would cause.
• You request it in writing and the federal agency or pass-through entity approves in writing.
• After soliciting several sources, competition is determined inadequate.

Keep records of the rationale for the method, the contractor selection and the basis for the price (2 CFR 200.318(i)). Above the simplified acquisition threshold, you need a cost or price analysis starting from an independent estimate (2 CFR 200.324(a)), and the federal agency or pass-through entity can ask to review the purchase before award (2 CFR 200.325(b)(2)). Check your award terms as well.

State, local and private buyers

State and local rules differ on what qualifies, the value that triggers a justification, who approves and whether a notice of intent must be posted. Some states post these notices on the portals in RFPhub’s state procurement portals directory. Private companies set their own rules in a purchasing policy. Check with your procurement office or legal counsel. This isn’t legal advice.

Sole source justification example

Adapt this outline to your organization’s form. The scenario is fictional: a county runs building permits on a vendor-hosted platform and wants residents to book inspections online.

The procurement process guide shows where sole sourcing fits alongside quotes, bids and RFPs.

Frequently asked questions

What is a sole source justification?

It’s a written explanation of why a purchase should go to one supplier without competition. It shows why only that supplier can meet the need, records the market research and explains why the price is reasonable.

What is the difference between sole source and single source?

Sole source usually means only one supplier can provide what you need. Single source usually means others could, but you chose one for a documented reason such as compatibility. Organizations and regulations use the terms differently, so check your own policy.

Is a vendor’s sole source letter enough?

No. The letter records the vendor’s own claim, which your market research has to test. Attach it as supporting evidence, but base the justification on what you found yourself.

Who approves a sole source justification?

Whoever your policy or the governing rules name, often at a more senior level as the value rises. In US federal buying, FAR 6.304 sets the approval levels.