Compare BOM quotes against the same approved bill of materials, quantity and delivery requirement. The lowest unit price is only comparable when the quoted part, condition, packaging and commercial scope are equivalent. Record exceptions before choosing a supplier.
Start with one controlled BOM revision
Give each supplier the same revision identifier and quote template. Keep manufacturer part numbers as text so spreadsheet software does not remove leading zeros or change long numbers. Separate the requested part from any proposed alternative.
- Manufacturer and full manufacturer part number, including suffixes.
- Quantity per assembly, build quantity and separately agreed spares or attrition allowance.
- Package, value, tolerance and relevant electrical or environmental requirements.
- Approved manufacturer list and substitution approval rules.
- Packaging, date-code, traceability and documentation requirements where applicable.
- Required delivery date, destination and quotation validity period.
Normalize every supplier response
| Field | Comparison check |
|---|---|
| Part identity | Match the full quoted part number to the requested one; flag every deviation. |
| Price basis | Identify currency, price per piece or pack, quantity break and exchange-rate date if conversion is needed. |
| Purchase quantity | Record minimum order quantity, order multiple and any excess stock you must buy. |
| Availability | Separate confirmed stock from estimated lead time and verify allocation assumptions. |
| Condition and packaging | Distinguish new, surplus or previously used material and confirm reel, tray or other packaging. |
| Included services | List testing, inspection, documentation, programming and packaging charges separately. |
| Commercial terms | Record delivery terms, payment terms, cancellation restrictions, returns and quote validity. |
A blank field is an unresolved item, not a zero cost or a promise of immediate availability. Ask for written clarification and retain it with the quotation.
Calculate cost for the quantity you will actually purchase
Use the purchased quantity after applying minimums and order multiples. Add the charges within the chosen comparison scope. Keep uncertain freight, taxes, duties and inspection costs visible as assumptions until confirmed.
Illustrative example only: the following quotes assume the same approved part and a purchase quantity of 1,000 pieces. These are invented numbers for explaining the calculation, not current supplier prices. Taxes and duties are excluded and would need separate treatment for an actual order.
| Cost item | Supplier A | Supplier B |
|---|---|---|
| Unit price | USD 0.87 | USD 0.82 |
| 1,000 pieces | USD 870 | USD 820 |
| Quoted freight | USD 35 | USD 110 |
| Agreed inspection charge | USD 25 | USD 40 |
| Total within this scope | USD 930 | USD 970 |
Supplier B has the lower unit price but the higher total in this example. Neither quotation should be selected on this calculation alone: part compliance, source evidence and delivery requirements still need to pass review.
Resolve technical and supplier risks before scoring price
Treat essential requirements as acceptance gates. A different qualification, package or temperature grade cannot be compensated for by a lower price. A supplier quality-system certificate and a product-specific certification answer different questions; record their scope and relevance rather than treating them as equivalent labels.
Engineering should approve substitutions against the actual design requirements. A footprint match or cross-reference listing alone does not establish electrical, software or reliability compatibility. Retain the approval and any validation requirements with the BOM revision.
For delivery-sensitive parts, review the assumptions in your lead-time and safety-stock planning. For assembly quotations, separately define PCB fabrication, assembly, programming, test coverage and DFM review scope.
Use tools to flag exceptions, then review the evidence
A spreadsheet can work for a small, controlled comparison. Larger BOMs may benefit from a sourcing or product-data system. Whichever tool is used, check part-number matching, pack-to-piece conversion, duplicate lines, missing quotes and revision changes. Do not accept automatically suggested alternatives without engineering approval.
- Import each quotation into the same column structure.
- Match line items and retain the original supplier text.
- Flag missing information and proposed alternatives.
- Calculate costs using an explicit quantity and currency basis.
- Resolve exceptions and record the final approval.
Prepare a reviewable sourcing request
Send the controlled BOM, build quantity, delivery destination and required date through our contact page. Ask for a written quotation that identifies availability assumptions, proposed alternatives, included services and unresolved requirements.
Frequently asked questions
Can I compare a reel price with a piece price?
Convert both to the same unit, but retain the required purchase quantity. A low price per piece may still require buying a full reel that exceeds the build requirement.
How should I handle a quotation with missing lines?
Mark those lines as unquoted. Compare the cost and delivery implications of completing the BOM from additional suppliers instead of treating the missing lines as free.
Should I choose the lowest total?
Only after the quotation meets the technical, sourcing and delivery requirements. Record remaining uncertainties and obtain the appropriate approval before ordering.
