Last updated: 2026-09-02 · 5 min read

How Do You Compare Injection Mold Quotations from Multiple Suppliers Without Making the Wrong Decision?

Compare mold quotations line by line — not by the total price — checking that each quote includes the same scope: cavity count, steel grade, mold base standard, hot runner brand, surface finish, tolerance specification and spare parts list. The lowest total price is often the lowest because something has been removed from the scope — a cheaper steel grade, no hot runner, no dimensional report, no spare parts.
When the scope is not identical, the price comparison is meaningless and the “savings” will be recovered in mold modifications, production defects or unplanned downtime.

Runner system — The channel network that delivers melt from the machine nozzle to each cavity. Cold runner: solidifies between shots, produces runner waste. Hot runner: stays molten, eliminates runner waste but adds $15k–$40k to mold cost. See also related guide.

Key Facts

  • Three cost tiers for custom injection molds from China: commodity molds (P20 steel, cold runner, DME/LKM base) at $3,000–10,000; engineering molds (H13/S136 steel, hot runner, SPI B2 finish) at $10,000–30,000; precision molds (NAK80/S136-ESR, valve gate, A1 polish, full dimensional report) at $30,000–80,000+.
  • Steel grade accounts for 20–35% of the mold cost; the mold base accounts for 15–25%; machining (CNC, EDM, grinding) accounts for 30–40%; assembly, tryout and dimensional inspection accounts for 10–15%.
  • A $2,000 difference in steel grade (P20 vs. H13) can mean a 3× difference in mold life: P20 at 100,000 shots vs. H13 at 500,000 shots. The per-part cost of the cheaper mold may be higher because the mold must be replaced or rebuilt sooner.

    • Runner system — The channel network that delivers melt from the machine nozzle to each cavity. Cold runner: solidifies between shots, produces runner waste. Hot runner: stays molten, eliminates runner waste but adds $15k–$40k to mold cost. The related guide covers adjacent topics.

    Quotation Comparison Checklist

    Line Item What to Check
    Cavity steel grade P20, H13, S136, NAK80 — verify the grade matches the required mold life and resin (corrosive, abrasive)
    Mold base standard LKM, DME, HASCO — the standard determines interchangerability and spare parts availability
    Hot runner system Brand (Yudo, Synventive, HRS, Mastip), number of drops, valve gate or open tip — price difference of $3,000–15,000
    Surface finish SPI A1, A2, B1, B2, C1, D3 — each step up in polish quality adds $500–2,000 to the mold cost
    Dimensional report Full CMM report with GD&T vs. drawing — some quotes exclude this to reduce cost, but it is the only way to verify the mold meets tolerance

    Hidden Cost Items That Are Often Excluded

  • Dimensional inspection and CMM report: a full first-article inspection costs $500–2,000 and takes 1–3 days. Some quotes exclude it to appear cheaper — the buyer discovers the need after T1 and pays for it separately at a higher cost.
  • Spare parts and maintenance kit: ejector pins, springs, cooling fittings and O-rings should be included in the quotation. When excluded, the buyer must order them later at a higher price and with longer lead time.
  • Engineering changes: the quotation should specify the cost of mold modifications after T1 — typically $200–500 per change for minor modifications (gate resize, ejector add) and $1,000–5,000 for major modifications (cavity re-cut, slider add). When the modification cost is not specified, the supplier has no incentive to control the mold design cost.

    • What This Means for Your Decision

    The decision should be based on the total cost of ownership — not the mold price alone. A $5,000 mold that lasts 100,000 shots costs $0.05 per shot in mold amortization; a $15,000 mold that lasts 500,000 shots costs $0.03 per shot. The more expensive mold is cheaper per part.
    The quotation should document the expected mold life, the steel grade and the maintenance schedule — so the buyer can calculate the per-part cost and make the decision based on data.

    Frequently Asked Questions

    How many quotes should you request before making a decision?

    Three quotes is the standard practice — enough to see the price range and identify outliers. More than five quotes wastes time for both the buyer and the suppliers. The goal is not to find the lowest price but to find the quote that offers the best value at the required quality level — and that requires comparing line items, not totals.

    Should you negotiate the price after receiving the quotes?

    Negotiation is appropriate when the scope is identical and the price difference is more than 15–20%. The negotiation should focus on scope adjustments — “Can you include the hot runner in the price?” or “Can you add the CMM report?” — rather than a flat price reduction. A flat price reduction without scope adjustment often means the supplier will cut corners somewhere else.

    What is the most common mistake buyers make when comparing quotes?

    Comparing total prices without verifying that the scope is identical. A $8,000 quote with P20 steel and no hot runner is not comparable to a $15,000 quote with H13 steel and a hot runner — the two molds will perform differently, last differently and cost differently per part. The first step in any quote comparison is to normalize the scope so the prices are comparable.

    Key Takeaways

    1. Compare mold quotations line by line — cavity steel, mold base, hot runner, surface finish, dimensional report and spare parts — not by total price, because the lowest total often excludes critical scope.
    2. Hidden cost items (CMM report, spare parts, engineering changes) are often excluded to appear cheaper — the buyer pays for them later at higher cost.
    3. The decision should be based on total cost of ownership (mold cost ÷ expected mold life = per-part amortization) — so the more expensive mold may be cheaper per part.

    Send aCatMould the part drawing and the competing quotations, and the comparison review identifies scope gaps, hidden exclusions and the per-part cost difference — so the mold decision is based on documented value, not the lowest number.

    Sources
    MoldMaking Technology — mold quotation comparison and evaluation
    Plastics Technology — understanding mold cost drivers
    SPE — mold procurement and quotation evaluation guidelines

    Sources: Plastics Technology · Plastics Technology Online · Society of Plastics Engineers (SPE) · ThomasNet