A plastic injection mold can cost between $5,000 and $100,000-plus, and most single-part production tools land between $10,000 and $40,000.

That’s the real range, and every figure in this guide stays a range on purpose — anyone quoting injection mold prices to the dollar without seeing your part design is just guessing.

What you can pin down is why a quote lands where it does: the steel grade, the SPI class, the cavity count, and the skilled labor that makes up more than half of the invoice. Read the next ten minutes and the next quote that crosses your desk will actually mean something.

4 Price Tiers Every Injection Mold Quote Falls Into

Mold pricing sorts into four tiers, and knowing which tier your part belongs in tells you more than any online calculator will.

  1. A simple single-cavity steel tool (Class 103/104) runs $5,000–$15,000 — P20 steel, straight-pull, no side actions (e.g. 10×10 mold)
  2. A standard production mold (Class 102/103) can run between $10,000–$40,000 — two to four cavities in P20, with some actions.
  3. A complex multi-cavity hardened tool (Class 101/102) can run between $50,000–$150,000+ — H13 or S7 steel, hot runner, slides and lifters.
  4. Specialty tooling for medical validation, optical parts, or high cavitation can run between $100,000–$500,000+.

Before any of those tiers comes the question of proving the design. Prototype tooling exists, usually quoted somewhere between $1,000 and $8,000, and you will see it offered. We don’t recommend it. When geometry needs proving before steel, 3D printed parts do that job faster and cheaper, and they don’t leave you holding a tool that is finished at 500 shots. Prove the design, then cut steel.

If you want one anchor number, a typical mold for a simple hand-sized part runs around $12,000. A two-part enclosure — top and bottom shells with bosses and snap fits — could run $8,000–$25,000 for the tool set, depending on size and geometry.  Those snap fits are undercuts, and undercuts cost money.

The tiers still hold up well enough to plan against. If your part has no undercuts and needs 50,000 lifetime pieces, you should not be staring at a six-figure tooling line. If you’re launching a program that needs a million parts a year, a $9,000 mold isn’t a bargain — it’s a tool that will die before the program hits stride.

The SPI Class Number Is Your Accountability Document

Every production mold quoted in the US should carry an SPI classification (the standard is SPI AN-102, from the Plastics Industry Association), and the class number is the difference between buying a rated tool and buying a promise.

  • Class 101 injection molds are rated for over 1,000,000+ cycles, and they come with hardened cavities and cores at 48 HRC minimum, hardened wear items on every slide and lifter, and guided ejection.
  • Class 102 covers up to 1,000,000 cycles in high-quality steel, built for tight tolerances and abrasive resins.
  • Class 103 covers up to 500,000 cycles and is the workhorse — it’s where most production tools in the field actually sit.
  • Class 104 covers up to 100,000 cycles, allows aluminum or mild steel cavities, and handles non-abrasive resins only.
  • Class 105 is a prototype tool, rated under 500 cycles, built however the parties agree.

A Class 105 tool can cost roughly 40–60% less than a Class 101 for the same part.

A Class 104 tool sold as ‘production tooling’ with no class on the quote looks like a bargain until it wears out at 80,000 shots.

The class callout on the RFQ is the accountability document — the same reason we’ve argued buyers should know who is actually cutting their steel. If a shop won’t put the number in writing, that silence tells you everything.

The Resin Chooses the Steel, and the Steel Sets the Price Floor

Why does the same part quote at $9,000 from one shop and $16,000 from another? Usually the steel — and the steel isn’t a preference, it’s a consequence.

P20 is the baseline: pre-hardened to 28–32 HRC, machines beautifully, takes a good polish, and lives comfortably in 500,000-cycle territory running PP, PE, or ABS. 718H is P20’s upgraded sibling — a few points harder, better polish, modest premium.

NAK80 steel sits at 37–43 HRC and gives you a uniform, carbide-free structure that allows a true SPI A-1 mirror polish. P20 and H13 physically cannot do that. Lenses, clear parts, and Class-A cosmetic surfaces have no other option.

Then we have the through-hardened grades.

We’ll start with H13, which heat-treats to 46–50 HRC, shrugs off thermal fatigue, runs from one to two million cycles, and will cost you typically 25–50% more than P20 once machining and heat treatment are counted.

S7 is shock steel at 52–58 HRC — the pick when fragile shut-off edges or slamming actions would chip anything softer.

420 stainless (S136) resists the hydrochloric acid that PVC outgasses at melt temperature; it runs 50–70% more than P20, but when dealing with corrosive resins there is no substitute.

The chain runs in one direction. Your resin chooses which steel you need; steel sets the floor on price.

Glass-filled and mineral-filled resins are abrasive, so hardened H13 stops being optional for every occasion. PVC grades are corrosive, so stainless stops being optional.

Need a mirror finish? That points to NAK80. You do not have to walk in knowing any of this — tell us the resin, the cosmetic requirement, the tolerances, and the annual volume, and we specify the steel that meets them. Just understand that once the resin is settled, most of the tool budget is settled with it.

The pre-hard versus through-hard fork is where the process cost lives. Pre-hardened steel arrives at working hardness — machine it once and finish it.

Through-hardened steel arrives soft, gets machined, goes out for heat treatment, comes back moved by a few thousandths, and then has to be finish-ground and EDM’d back to dimension.

Largest Cost Drivers for Injection Mold Pricing

Cavitation and part geometry are the 2 biggest levers, but it doesn’t scale the way most buyers expect. Let’s say you have an 8-cavity mold. It’s going to run 3–4× the cost of a single-cavity one, not 8×.

The base, ejection, and cooling systems are shared. Each added cavity will add roughly 30–50% to overall tool cost while dividing your per-part price at volume.

One example from the field: a 2-cavity automotive interior trim tool made in H13 came in at around $16,500, and the second cavity by itself accounted for roughly $5,500 of that.

A hot runner will add $15,000–$40,000+ up front; however, it pays you back through eliminated runner scrap and faster cycles.

Another working example: a 4-cavity valve-gate upgrade adds about $50,000 but also saves about $0.08 per part — break-even near 625,000 parts. Below that volume, cold runner wins out.

Surface finish stacks on top of everything else. Standard commercial finish is already baked into the price, but an SPI A-2 diamond polish adds $500–$3,000 (and forces NAK80 or S136). A true A-1 mirror adds $1,000–$5,000, and texture adds $300–$2,000.

Tight tolerances multiply everything even further.

Tolerances of ±0.001 in. add premium EDM time, slower machining, and more metrology.

Part size scales nearly linearly: more steel requires a bigger base, which means a bigger press.

Post-build modifications are the DFM argument in dollars. A minor change — rib height, gate opening — runs $300–$1,500 and takes 3–7 days. Moving a parting line or adding a slide runs $2,000–$8,000 and takes 2–4 weeks. Hardened steel locks the design. Fix the geometry on paper, where revisions are free.

Where the Money Actually Goes

Skilled labor is 50–60% of the price of a mold. Not the steel — the people.

Remember you’ll be paying skilled CNC and EDM operators, moldmakers hand-fitting and spotting the parting line, followed by polishers putting hours into surfaces no machine can finish. Raw steel is only 15–25%.

Design and engineering fill in much of the rest. A simple mold takes 20–40 engineering hours; a complex one takes 200 or more, at $90–$150+ an hour — call it $2,000–$5,000 on the low end and $15,000–$30,000 for demanding programs. Mold flow analysis adds $1,500–$3,000 and is the cheapest insurance in the building.

Sinker and wire EDM for sharp internal corners and deep ribs commonly add $1,000–$5,000. Then come T1 and T2 sampling trials, where tuning for shrink and debugging absorb another $1,000–$5,000 of shop time before production parts ship — cost that already sits inside a quoted tool price rather than arriving as a later bill.

That’s the accounting answer. The physics answer is better.

Production molds are a precision pressure vessel: they can hold tolerances into the thousandths while absorbing thousands of PSI of injection pressure and a complete thermal cycle every 15–60 seconds. They can do that for hundreds of thousands to millions of cycles, while cooling circuits, ejector pins, vents, and slides all keep working in sync.

Machining a block into a shape is the cheap part. Building it to survive that is the invoice.

Maintenance, Lead Times, and What Sits Outside the Tooling Quote

A tooling quote from a reputable domestic shop covers the tool and the work it takes to make that tool produce good parts: sampling, tuning for shrink, and the adjustments that come out of T1 and T2. We do not bill those separately, and we are not aware of a shop in this region that does. The one thing worth carrying a contingency for is a design change you discover during sampling — a gate that has to move, a rib that has to come down, a wall that has to thicken. That is real, and it is usually a few thousand dollars. It is not a percentage of your tool.

After launch, maintenance is what keeps the class rating honest. A Class 101 tool reaches its million-cycle rating because someone cleans it, greases it, and replaces wear items on schedule. Skip that and the same tool dies at 400,000. On tools we build, that upkeep is covered inside the warranty period; it only becomes a chargeable repair once a mold is running well beyond it. Budget the attention, not a line item.

On timing: production steel tools are sampling in 5–8 weeks, and hardened multi-cavity work often runs 6–10. The amortization math is what makes all of it worth doing — a $7,000 mold across 300,000 rated shots is about $0.04 per part. The tool is expensive. The parts aren’t.

Invoice Price and Landed Cost Are Different Animals

Offshore injection mold quotes often come in up to 30–65% below US quotes.

Fully landed, that gap shrinks to closer to 35–50%. A production tool can weigh 1,700+ lbs, so freight adds $800–$2,000+. The larger line is tariffs. An injection mold is an article made almost entirely of steel, which puts it in the top Section 232 tier at 50%, and since April 6, 2026, that duty is assessed on the full customs value of the tool rather than on its steel content alone. China-origin tooling can carry Section 301 duties on top of that.

Steel tariffs raised input costs for everyone, domestic builders included. The 2026 restructuring squeezed the cheap-import math hardest, because a finished imported tool is now taxed on what the whole tool is worth instead of on the metal inside it.

Some of the Tier-1 offshore shops genuinely match Western quality — we’ve managed overseas tool builds ourselves, in person, and the good ones are truly great partners for us.

The problems live in the gap between the invoice and your landed cost: add in 3–5 weeks of sea freight, revision loops across remote time zones, and potential requalification when a tool arrives out of spec. Plus your tooling data is sitting on someone else’s server in a foreign country.

A domestic tool is a tool you can stand next to while it’s being fixed. Price it however you want, but price it.

The Injection Mold Cost Questions Buyers Keep Asking

  1. What does a plastic injection mold cost? Between $5,000 and $100,000+, with most single-part production tools landing between $10,000 and $40,000. Class, steel, cavitation, part geometry, and finish set where you fall in that range.
  2. Why are injection molds so expensive? Because 50–60% of the price is skilled labor — design, CNC and EDM machining, hand-fitting, and polishing hardened tool steel to tolerances measured in thousandths — and the finished tool has to survive full injection pressure and thermal cycling for up to a million cycles.
  3. What is the life expectancy of a plastic injection mold? You’re looking at anywhere from under 500 cycles for a Class 105 prototype tool to more than a million cycles for a maintained Class 101 mold.
  4. What is the cheapest material for injection molding? Polypropylene is one of the cheaper resins — but watch the question, because it conflates resin cost with tooling cost. Cheap resin doesn’t mean a cheap mold. Mineral-filled PP is inexpensive per pound, but it still requires hardened H13 tooling because the filler is abrasive.
  5. What are the drawbacks of injection molding? Upfront tooling cost and lead time. You’re committing five figures and 8–10 weeks before the first sample parts exist. The trade flips at volume — a 30-gram ABS housing costs about $52.50 per part at 100 units and about $0.45 at a million. If your volumes never climb, the mold never pays for itself, and an honest shop will tell you that before you cut steel.

Need help estimating the cost of your own mold build? Please use our free quote form, and our product specialist, Steve, will reach out as soon as possible.