An injection molding quote for production parts should be based on a controlled part definition, expected volume, quality requirements, and clearly stated supply scope. This guide focuses on quoting molded parts and related production work. A separate mold-tool quotation covers the tooling design and build scope, which should not be confused with the recurring part price.
Prepare a controlled part package
Send the same current 3D model and 2D drawing revision to each supplier. Include the resin supplier and grade where known, color, finish, critical dimensions, assembly interfaces, intended use conditions, and target-market requirements. If a material or design alternative is acceptable, define how the supplier should identify and price it rather than allowing silent substitutions.
State the volume and order assumptions
Share the expected first order, annual forecast range, order frequency, launch ramp, and any seasonal or service-part demand. A quote based on a single batch may not use the same assumptions as a longer production program. Ask suppliers to state the quantity breaks and minimum order assumptions behind each price.
Define what the supplier must include
List whether the requested scope includes material procurement, molding, trimming, finishing, printing, assembly, inspection, packaging, labeling, and delivery. Identify the production site and any customer-supplied parts or tooling. State who owns the mold, who maintains it, and whether tool costs, sampling, or engineering work should appear as separate line items.
Specify quality and sample requirements
Identify critical-to-quality features, inspection methods, sample quantities, appearance criteria, functional checks, and any reports needed for approval. Ask the supplier to separate the cost and timing of samples, validation, or testing from routine production where applicable. Requirements should match the actual part and market; a general quality claim is not a substitute for defined acceptance criteria.
Ask suppliers to show quote assumptions
- Unit price by the requested volume break, currency, quote basis, and validity period.
- Material grade, color, finish, and any permitted alternatives used for the estimate.
- Tooling, setup, engineering, sampling, inspection, and secondary-operation costs shown separately where relevant.
- Estimated lead times and the assumptions for tool readiness, material availability, sample approval, and production start.
- Minimum order, packaging, delivery terms, exclusions, and any items requiring customer supply or approval.
Compare offers on the same basis
Put each supplier’s assumptions beside the request and mark every difference before comparing unit prices. Resolve gaps in material, included operations, inspection, packaging, tooling, or delivery scope. Ask for a revised quote when the supplier’s assumptions differ from the controlled RFQ; do not treat an unpriced exclusion as included work.
For a project-specific manufacturing review, see DAYIN’s custom plastic injection molding service. For tooling-specific pricing and deliverables, see the injection mold quote comparison guide. Submit the drawing, resin, forecast and scope through Contact DAYIN.