Supplier due diligence checklist for procurement and project teams.
Supplier due diligence should be proportional to the value, criticality and risk of the requirement. Buying standard stationery from a local vendor does not justify the same review as appointing a contractor responsible for safety-critical equipment or a large imported delivery.
1. Verify legal identity
Confirm the supplier's legal name, registration information, trading name where relevant, physical presence and authorised representatives. Ensure the quotation, bank details, contracts and supporting records all refer to the same entity.
2. Understand ownership and conflicts
Identify directors, members or relevant ownership information and assess declared conflicts or related-party relationships. In regulated or public procurement, use the declarations and checks required by the applicable process rather than inventing an informal substitute.
3. Check whether the supplier can finance delivery
For material contracts, consider whether the supplier can fund stock, labour, imports and subcontractors before payment. Useful evidence may include financial statements, trade references, supplier terms, banking confirmation, credit information or contract-specific guarantees, depending on the procurement context.
4. Verify technical capacity
Ask for evidence that matches the actual work: product datasheets, qualifications, licences, professional registrations, test records, equipment lists, key personnel CVs, OEM letters, workshop capacity or implementation methodology.
Do not reward large volumes of irrelevant documentation. Map evidence to the critical technical requirements.
5. Test previous experience accurately
References should be specific enough to verify what the supplier actually delivered. Check project scope, client, date, value or scale where relevant, outcome and contactability. Distinguish company experience from individual team experience.
6. Assess quality controls
Determine how the supplier prevents, detects and corrects defects. Depending on the work, this can include inspection plans, calibration, test certificates, quality procedures, traceability, serial-number control, document control or formal quality-management certification.
7. Review supply-chain dependencies
Ask which parts of the offer depend on other suppliers, manufacturers, imports or subcontractors. A supplier may be strong operationally but still exposed to a single unavailable component or unrealistic manufacturer lead time.
8. Check logistics and service reach
Confirm where stock is held, how delivery is performed, who carries insurance, whether offloading is included, what happens if goods are damaged and how remote service calls will be supported.
9. Review warranty and after-sales support
Understand who honours the warranty: the bidder, distributor, local service agent or overseas manufacturer. Confirm turnaround expectations, exclusions, parts availability and escalation paths.
10. Check compliance relevant to the work
Registrations, licences, safety files, insurance, professional credentials, tax information and B-BBEE evidence may all matter, but relevance depends on the procurement. A generic compliance folder should not replace a requirement-specific review.
11. Use a risk-based approval level
Classify suppliers by consequence of failure. A critical supplier may justify financial review, reference calls, site inspection, sample testing and executive approval. A low-value commodity supplier may only need basic verification and performance monitoring.
12. Continue due diligence after appointment
Supplier assessment is not complete at onboarding. Track quality, on-time delivery, responsiveness, non-conformances, invoice accuracy and warranty performance. This produces evidence for future sourcing decisions instead of restarting from anecdote every time.
The objective is not paperwork; it is reduced delivery uncertainty
Good due diligence makes the risk visible before award. Pair it with a clear technical evaluation matrix so commercial attractiveness does not obscure unsupported technical claims.