Sole source
A sole source procurement awards a contract without competition because only one supplier can meet the district's requirement. It is a narrow exception to competitive procurement, and the burden of justifying it sits with the district rather than with the vendor.
| Ground asserted | Evidence required | How it fails on audit |
|---|---|---|
| Only one supplier exists | Documented market research showing no alternative meets the requirement | Two competitors are found in ten minutes of searching |
| Compatibility with existing infrastructure | A technical statement of why an alternative cannot interoperate | The incumbent publishes an open API, so alternatives can interoperate |
| Emergency or public exigency | Contemporaneous record of the emergency and the timeline it imposed | The emergency was a missed renewal date |
| Proprietary requirement | The specification derives from a legal or curricular mandate | The specification was written from the vendor's own feature list |
| Standardisation across sites | Board-adopted standardisation policy predating the purchase | The policy was adopted to justify this purchase |
| Switching cost | A costed comparison including the cost of not switching | Inconvenience is not impossibility, and auditors know the difference |
Sole source is not single source
District policies conflate these constantly and auditors do not.
Sole source means the market contains one supplier capable of meeting the requirement. It is a fact about the market, provable or not.
Single source means the district has chosen one supplier although others could meet the requirement — for standardisation, continuity, staff familiarity or preference. That is a defensible procurement decision in many jurisdictions, but it usually requires a different authority and different documentation, and calling it sole source when it is single source is the fastest route to a finding.
The practical test is a question asked out loud in a meeting: if this vendor doubled its price tomorrow, would we have any alternative at all? If the honest answer is that alternatives exist but switching would be painful, this is single source and should be documented as such.
What federal funds change
Where federal money pays for a purchase, non-competitive procurement is permitted only in specific circumstances: the item is genuinely available from a single source; there is a public exigency or emergency that will not permit delay; the awarding or pass-through agency expressly authorises it in response to a written request; or competition was solicited and found inadequate.
Two consequences follow. Prior written approval may be required, which takes time nobody has budgeted. And the record has to be contemporaneous — a justification written after the award, once someone asks, is worth considerably less than one written before it.
The documentation that survives review is unglamorous: a description of the requirement in functional terms, the market research performed with dates and sources, the reason each alternative was rejected, a price reasonableness analysis, and the approvals at the level your policy requires.
Kastr is not a sole source
We should say this outright, because vendors in this category write sole-source justification letters for districts and it is a practice worth naming.
Several features of ours appear to be genuinely uncommon — a cost-and-reach preview before sending, a signed migration receipt with a per-file hash manifest, tenant isolation enforced at the database layer under a non-owner role with a leakage suite in CI, an open-source CLI and MCP server under MIT licence. Uncommon is not unique, and none of it makes us the only vendor able to send a district's families a message.
If any vendor drafts your sole-source justification, read what they wrote. The specification will describe their product rather than your requirement, and that is the exact pattern an auditor is trained to spot. A functional requirement says "audience must resolve against current enrolment at send time". A vendor-written one names a feature only one product happens to have.
The honest route for a district that wants us is an ordinary competitive process, or a co-operative vehicle we do not currently hold. We would rather lose a competition than win an award that generates a finding for the person who signed it.
This entry describes what the rule says. Whether and how it applies to your district is a question for your own counsel, not for a vendor.
Questions people actually ask
What is the difference between sole source and single source?
Sole source means only one supplier in the market can meet the requirement. Single source means the district chose one supplier although others could have met it, usually for standardisation or continuity. They require different authority and different documentation, and conflating them is a common audit finding.
Can a district sole-source a product it already uses?
Incumbency alone is not a ground. Continuity and switching cost are real considerations, but they describe a single-source decision rather than a sole source, unless no alternative can meet the requirement at all.
Does federal funding change sole-source rules?
Yes. Federal procurement standards permit non-competitive awards only in specified circumstances, may require prior written approval from the awarding or pass-through agency, and expect contemporaneous documentation including a price reasonableness analysis.
What documentation supports a sole source award?
A functional description of the requirement, the market research performed with dates and sources, the reason each alternative was rejected, a price reasonableness analysis, and approval at the level your policy sets — all written before the award rather than after a question about it.
One price. Every feature. Locked for three years.
$3.50 per student per year under 5,000 students. No tiers, no add-on modules, no per-message fees. Published on the site because you should not have to book a call to learn a price.