How to choose · Procurement and suppliers
How to choose a supplier and run due diligence
Last updated 25 October 2026 · 1 source listed · Reading time about 3 minutes
Short answer
Select suppliers using weighted criteria agreed before looking at quotes: capability, quality, financial stability, security and compliance, delivery reliability, and total cost of ownership. Verify claims with references, site visits or audits and check legal standing and sanctions screening. Document the decision so it can be explained and repeated. Avoid choosing on unit price alone.
Who this is for: A procurement or operations lead selecting a supplier for goods or services and wanting a structured way to compare and vet candidates.
What to evaluate
Capability and capacity
A supplier must be able to meet volumes and specifications now and as demand grows.
How to check: Request capacity details, sample work and evidence of similar projects.
Quality systems
Consistent processes reduce defects, rework and disputes.
How to check: Ask for quality certifications, inspection procedures and defect handling records.
Financial stability
A supplier that fails mid-contract can disrupt your operations.
How to check: Review financial statements or credit reports and look for dependency on a few customers.
Compliance and ethics
Legal, labour, environmental and anti-corruption failures create liability for the buyer.
How to check: Request policies, certifications and check sanctions and debarment lists.
Information security and data handling
Suppliers with access to systems or data expand your risk surface.
How to check: Use a security questionnaire and ask for relevant certifications or audit reports.
Total cost of ownership
Price, logistics, defects, support and switching costs together determine value.
How to check: Model costs over the contract life rather than comparing unit prices.
Comparison
| Method | Good when | Watch out for |
|---|---|---|
| Questionnaire | Screening many candidates quickly | Self-reported answers may be optimistic |
| Reference checks | Confirming delivery and service history | References are usually selected by the supplier |
| Site visit or audit | Critical or high-risk suppliers | Time and cost to arrange |
| Third-party reports | Assessing finances and legal standing | Information may lag behind reality |
Decision worksheet
Rate up to three options against this guide’s own criteria. It runs in your browser and saves only on this device. It is a thinking aid, not a recommendation.
1. Have you checked each criterion?
0 of 6 criteria checked.
2. Compare options (0 = fails or unknown, 3 = meets it well)
| Criterion | |||
|---|---|---|---|
| Capability and capacity | |||
| Quality systems | |||
| Financial stability | |||
| Compliance and ethics | |||
| Information security and data handling | |||
| Total cost of ownership | |||
| Total (max 18) | 0 | 0 | 0 |
Questions to ask before you commit
- What evidence shows you can meet our volume and quality needs?
- Which certifications do you hold and when were they last audited?
- Who are your main customers and can we speak with some?
- How do you handle defects, delays and disputes?
- What subcontractors do you use and how are they managed?
- How do you protect information and what happens in a security incident?
- What is your business continuity plan if a site or key person is lost?
- What changes could affect pricing during the contract?
Typical trade-offs
Single source supplier
- Upside
- Stronger relationship and volume leverage
- Downside
- Higher disruption risk if the supplier fails
Multiple suppliers
- Upside
- Resilience and competitive tension
- Downside
- More management effort and less volume leverage
Local supplier
- Upside
- Shorter lead times and easier oversight
- Downside
- May cost more or have limited capacity
Common mistakes
- Choosing on lowest quote without checking capability; evaluate total cost and risk.
- Skipping references and site checks for critical suppliers.
- Failing to document selection criteria, which makes decisions hard to defend.
- Not checking subcontractors who deliver part of the work.
Related questions
How much due diligence is enough?
Scale it to the risk and value of the relationship. Low-value commodity purchases may need only basic checks, while critical suppliers or those handling sensitive data warrant deeper review, including audits and financial analysis. Classify suppliers by risk and apply matching levels of scrutiny. Revisit periodically because suppliers change over time.
What is total cost of ownership?
It includes the purchase price plus costs across the item or service life: delivery, installation, training, maintenance, downtime, quality problems, disposal and switching. A cheaper unit price can hide higher lifetime costs. Build a simple model with the main cost drivers and compare suppliers on that basis rather than on price alone.
Should I use a formal tender?
Tenders give transparency and competition, and may be legally required for public bodies or above certain value thresholds. For private firms, a structured request for proposals can offer similar benefits. Formal processes take time, so match the approach to the value and complexity of the purchase and follow your internal policy and any legal rules.
How do I handle conflicts of interest?
Require declarations from people involved in selection, separate duties where possible, and record decisions with reasons. Gifts and hospitality rules help prevent undue influence. If a conflict exists, the individual should step back from the decision. Clear policies and training reduce risk and protect both the company and staff. Review declarations at regular intervals rather than once, since relationships and shareholdings change, and make sure staff know how to raise concerns confidentially.
Sources and further reading
These pages were reachable when we last checked. They informed definitions and rules referred to above; they do not endorse this guide. Where rules differ by country, check the authority for your location.
- US Small Business Administration — US SBA, retrieved 27 October 2026
Related guides
Comparison · Procurement and suppliers
Competitive tender versus framework agreements versus spot buying
Tenders suit large, complex or high-value purchases where transparency and competition matter. Framework agreements pre-qualify suppliers and agree terms so individual orders are quicker. Spot buying suits low-value or urgent needs but can lack leverage and control. Choose by value, complexity, frequency, legal rules and the need for supplier relationships, and keep records for accountability.
Problems & fixes · Procurement and suppliers
Handling supplier problems: late deliveries, quality failures and disputes
Handle supplier problems by documenting the issue, checking the contract for remedies, communicating promptly and escalating in stages. Distinguish one-off errors from systemic failures, quantify the impact and agree a corrective action plan with dates. Keep contingency options available. Seek legal advice for serious breaches, and review the relationship after resolution rather than only reacting.
How to choose · Professional services
How to choose a business process outsourcing partner
Select a partner by testing process maturity, relevant references, security and continuity controls, the stability and training of the delivery team, and how well governance will work day to day. Start from a clear process definition and measurable service goals. A pilot with real volumes tells you more than any presentation.
How to choose · Professional services
How to choose a translation provider for business documents
Choose a provider by confirming language pair and subject expertise, the review process, confidentiality terms and how terminology is managed. Ask who actually translates, whether a second linguist reviews the work and what quality standard applies. For legal, medical or regulated content, verify credentials and any certification or sworn-translation requirement in the destination country.
Comparison · POS systems
Cloud POS versus on-premise POS
Cloud POS offers remote access, automatic updates and quicker setup but relies on connectivity and a subscription. On-premise systems run locally with fast response and independence from the internet but need servers, backups and technical support. Many modern hybrids cache locally. Choose according to connectivity reliability, technical capacity, number of sites and tolerance for vendor dependence.
How to choose · Business finance
How to choose between business loan types
Match the product to the need. Term loans suit one-off investments with predictable repayment, revolving credit lines suit uneven cash flow, and asset-backed products tie borrowing to equipment or invoices. Compare the total cost of borrowing, security required, personal guarantees, repayment flexibility and fees. This describes how to evaluate options and is not personal financial advice; consult a qualified adviser.
All Procurement and suppliers guides · All Business operations