SRCSourcing & procurementStop 3 of 9
Supplier selection & TCO
Choosing suppliers on total cost of ownership and a balanced scorecard, not on the lowest quoted price.
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Supplier selection usually follows a funnel:
- RFI (request for information): who could do this? Capabilities, certifications, capacity, financial health.
- Qualification: audits, samples and trial orders to check quality and reliability.
- RFQ or RFP: an RFQ asks for prices on a fixed specification; an RFP asks suppliers to propose a solution, such as a logistics service. Reverse auctions suit simple, well-specified items.
- Award and contract.
The trap is choosing on unit price. Total cost of ownership (TCO) adds everything the purchase really costs:
| Supplier A (overseas) | Supplier B (domestic) | |
|---|---|---|
| Unit price | ₹100 | ₹108 |
| Freight and duty | ₹9 | ₹2 |
| Extra safety stock for a long, variable lead time | ₹4 | ₹1 |
| Defects, rework and inspection | ₹3 | ₹1 |
| Total per unit | ₹116 | ₹112 |
The supplier that looks ₹8 cheaper on price ends up ₹4 more expensive per unit. TCO can also include payment terms, currency risk, switching costs and the risk of a disruption.
After the award, a supplier scorecard keeps score over time, typically on quality (defect rate), delivery (on time, in full), cost, responsiveness, and increasingly risk and ESG. Scorecards drive reviews, improvement plans and future volume allocation.
Words to use
- Total cost of ownership (TCO)
- All costs of buying and using an item: price, freight, duties, inventory, quality and risk.
- RFQ vs RFP
- Price quote for a defined spec, versus a proposal for how to solve a need.
- Supplier scorecard
- Regular ratings of a supplier on quality, delivery, cost, service, risk and ESG.
Weighted scoring
- Choose the criteria and agree their weights before seeing any bids.
- Define what each score means (for example, delivery 9 = 98% on time in trial orders).
- Score each supplier on evidence: audits, samples, references, TCO.
- Multiply by the weights and add up.
| Criterion | Weight | Supplier A | Supplier B |
|---|---|---|---|
| Quality (audit, samples) | 30% | 7 | 8 |
| Total cost of ownership | 30% | 6 | 8 |
| Delivery (lead time, reliability) | 20% | 6 | 9 |
| Technical capability | 10% | 8 | 7 |
| Risk and ESG | 10% | 5 | 8 |
| Weighted score | 6.4 | 8.1 |
B wins clearly, although A scores higher on technical capability. The TCO score reflects the full cost comparison (₹112 against ₹116 per unit in the gist), not the unit price.
Building the TCO
TCO adds up costs before, during and after the purchase:
- Before: finding and qualifying the supplier, samples, audits, tooling.
- During: price, freight, duties, packaging, payment terms, currency.
- After: inspection, defects and rework, warranty claims, extra inventory for long or unreliable lead times, disposal.
Not every cost is known exactly; reasonable estimates are far better than leaving them out.
Scorecards after the award
| Measure | Target | This quarter |
|---|---|---|
| On time, in full (OTIF) | 95% | 94% |
| Defects (parts per million) | 500 | 1,200 |
| Price against contract | 100% | 100% |
| Responsiveness to issues | Within 48 hours | 72 hours |
| Corrective actions closed | 100% | 60% |
A scorecard like this one triggers a review: quality is well below target, and corrective actions aren’t being closed. Scores feed volume allocation, so good performance earns more business.
Should-cost: knowing what it ought to cost
A should-cost (or clean-sheet) model builds the price bottom-up: material weight × material price, machine time × machine rate, labour, overhead, scrap, packaging, freight and a fair margin. Comparing it with the quote shows where the gap is, which turns negotiation from haggling into a discussion of specific cost elements, such as “your scrap rate assumption is twice the industry norm.”
When auctions work and when they backfire
Reverse auctions, where suppliers bid prices down in real time, work well for well-specified items with several qualified suppliers and low switching costs: leverage items. They backfire for strategic categories: suppliers who feel squeezed hold back innovation, capacity and priority when supply is short, and the winning bid may come from a supplier who can’t sustain it.
Qualification in regulated industries
In automotive, the Production Part Approval Process (PPAP) requires suppliers to prove their process makes conforming parts at volume, with documented measurements, process controls and failure-mode analysis, before production starts. Pharmaceuticals, food and aerospace have similar regimes. Qualification takes months, which is why second sources must be qualified before they are needed.
Due diligence beyond price
Supplier selection increasingly includes legal duties: forced-labour import rules such as the US Uyghur Forced Labor Prevention Act, the EU’s corporate sustainability due diligence directive, and customers’ own codes of conduct. Selection therefore checks labour practices, environmental compliance and the supplier’s own sources, not only its factory gate.
Biases that skew selection
- Incumbent bias: the current supplier is judged on its relationship, newcomers on their price.
- Price anchoring: the lowest quote dominates the discussion even when it scores poorly on TCO.
- Weights chosen after scoring, to justify a favourite.
- Halo effects: one impressive factory tour colours every score.
Fixed criteria, evidence-based scoring and cross-functional panels (procurement, quality, engineering, finance) reduce them.
Interview kit
Practise it out loud
Answer each question yourself before opening the model answer.
I’d select suppliers through a funnel, RFI, qualification, then RFQ or RFP, and compare finalists on total cost of ownership: price plus freight, duties, the inventory needed for their lead time and reliability, quality costs, payment terms and risk. The cheapest quote often isn’t the cheapest supplier. After the award, a scorecard on quality, delivery, cost, service, risk and ESG keeps performance visible.
An overseas supplier quotes ₹100 and a domestic one ₹108. How do you decide?
Build the total cost: freight and duties, the extra safety stock for a longer and more variable lead time, quality costs, payment terms and currency risk. In many cases the overseas option’s advantage shrinks or disappears. Then weigh risk and flexibility, such as how quickly each can respond to demand changes.
What would you put on a supplier scorecard?
Quality (defect rate, returns), delivery (on-time in-full, lead-time reliability), cost (price versus market, cost-reduction ideas), responsiveness and collaboration, plus risk and ESG indicators. Weight them by category and review them regularly with the supplier.
Connected stops
Where this idea feeds in, or gets its inputs from.
Sources and further reading
- Ellram, L. M. (1995). Total cost of ownership: an analysis approach for purchasing. International Journal of Physical Distribution & Logistics Management, 25(8), 4–23.
- Monczka, R. M., Handfield, R. B., Giunipero, L. C. & Patterson, J. L. Purchasing and Supply Chain Management. Cengage Learning.