Injection Molding Costs: Complete Breakdown (2026)

Why Understanding IM Cost Structure Matters

Injection molding is the most cost-effective process for producing plastic parts at scale - but only if you understand the cost structure. A part that costs $0.15 each at 100,000 units can cost $150 each at 10 units, because tooling dominates the economics at low volume. This guide breaks down every cost component so you can make informed make-vs-buy and mold-vs-print decisions.

Section 1 of 8

The Four Cost Components

Every injection-molded part's landed cost consists of four buckets. Understanding each is essential for accurate quoting.

Tooling (NRE)

The mold itself - design, machining, texturing, and qualification. This is the single largest upfront investment.

1.1

Material

Resin cost per part, determined by part weight and resin price per pound.

1.2

Production

Machine time, labor, secondary operations, and quality inspection.

1.3

Overhead

Mold maintenance, storage, engineering changes, and logistics.

1.4

Pro Tip

At low volumes (<1,000 parts), tooling dominates total cost. At high volumes (>100,000), material and cycle time dominate. Know which phase you're in to optimize the right lever.

Section 2 of 8

Tooling Costs: The Biggest Line Item

Mold cost is the single largest upfront investment in injection molding. It varies by 50× depending on part complexity, steel grade, number of cavities, and geography.

Mold Class	SPI Classification	Steel	Expected Life	Cost Range
Prototype (soft tooling)	Class 105	Aluminum 7075 or P20 pre-hard	500–5,000 shots	$2,000–$10,000
Low-volume production	Class 104	P20 pre-hardened steel	10,000–100,000 shots	$8,000–$30,000
Mid-volume production	Class 103	H13 or S7 hardened steel	100,000–500,000 shots	$25,000–$75,000
High-volume production	Class 102/101	H13 hardened, chrome-plated	500,000–1,000,000+ shots	$50,000–$200,000+

Undercuts and side actions

Each side-pull or lifter adds $2,000–$8,000 to the mold. A simple open-and-shut mold (no side actions) is generally the most cost-effective option.

2.1

Multi-cavity layouts

A 4-cavity mold costs ~2.5× a single-cavity mold, but produces 4× the parts per cycle - it pays for itself above ~50,000 units.

2.2

Tight tolerances

Holding ±0.001″ on a molded feature requires tighter mold steel tolerances (±0.0005″), which means EDM finishing and longer polish time.

2.3

Texturing

Chemical etch textures (MT series) add $500–$3,000 depending on area and depth. Laser texturing for finer patterns costs more.

2.4

Hot runners

A hot runner system ($5,000–$15,000) eliminates the cold runner sprue, saving 10–30% material and reducing cycle time - justified above ~25,000 parts.

2.5

Pro Tip

Don't buy a Class 101 mold for 10,000 lifetime parts. A $5,000 aluminum prototype mold will serve you fine - and you can transition to steel later if volumes ramp.

Section 3 of 8

Material (Resin) Costs

Material cost per part = (part weight + runner weight) × resin price per gram. Runner weight is recyclable with a granulator (regrind), but typically limited to 15–25% regrind ratio for structural parts.

Resin	Price ($/lb)	Density (g/cm³)	Typical Applications
ABS	$1.00–1.50	1.04	Consumer electronics, housings, toys
Polypropylene (PP)	$0.60–1.00	0.90	Packaging, living hinges, containers
Nylon 6/6 (PA66)	$1.50–3.00	1.14	Structural clips, gears, under-hood auto
Polycarbonate (PC)	$1.80–3.00	1.20	Lenses, transparent housings, medical
PC/ABS blend	$2.00–3.50	1.10	Laptop housings, automotive interior
POM (Delrin/acetal)	$1.50–2.50	1.41	Gears, clips, precision mechanical
Glass-filled nylon (PA66-GF30)	$2.00–4.00	1.35	High-stiffness structural, brackets
PEEK	$50–80	1.30	Aerospace, medical, semiconductor

Example: A 25-gram ABS housing with a 5-gram cold runner. • Total shot weight: 30 g (0.066 lb) • ABS price: $1.25/lb • Material cost per shot: $0.083 • With 20% regrind: effective cost ~$0.070/part Material cost is usually 10–30% of total part cost at production volumes. It becomes a larger share for high-volume commodity parts (where mold cost is fully amortized) and a smaller share for low-volume specialty parts.

Pro Tip

Buying resin in bulk (pallet quantities, 2,000+ lb) typically saves 10–20% vs. small-lot pricing. Always negotiate at volume.

Section 4 of 8

Production Costs (Machine + Labor)

Machine rate is quoted per hour and depends on press tonnage (which is determined by projected area and packing pressure).

Press Size (tons)	Hourly Rate	Typical Part Size
50–100 tons	$40–60/hr	Small connectors, clips, knobs
100–300 tons	$60–100/hr	Housings, covers, brackets
300–500 tons	$100–150/hr	Large enclosures, panels
500–1,000 tons	$150–250/hr	Automotive bumpers, large bezels

Cycle time (injection + cooling + ejection) directly determines throughput. A 30-second cycle on a $80/hr press produces 120 parts/hour at $0.67/part machine cost. Cut cycle time to 20 seconds and that drops to $0.44/part - a 34% reduction. The primary lever for cycle time is cooling time, which is driven by the thickest wall section. Every 0.5 mm of excess wall thickness adds ~5–10 seconds of cooling. This is why DFM rule #7 (uniform wall thickness) matters so much for molded parts.

Pro Tip

Cycle time is the hidden lever. Every 0.5 mm of excess wall thickness adds ~5–10 seconds of cooling. Uniform wall thickness is the single best DFM optimization for injection molding.

Section 5 of 8

Total Cost Per Part at Different Volumes

Real example: a 30-gram ABS consumer electronics housing, 120 mm × 80 mm × 25 mm, with two side actions and MT-11010 texture on the A-surface.

Volume	Mold Type	Mold Cost	Part Cost	Amortized Mold/Part	Total $/Part
100	Aluminum prototype	$5,000	$2.50	$50.00	$52.50
1,000	Aluminum prototype	$5,000	$1.80	$5.00	$6.80
10,000	P20 steel (Class 104)	$18,000	$0.95	$1.80	$2.75
50,000	H13 steel (Class 103)	$35,000	$0.70	$0.70	$1.40
250,000	H13 4-cavity (Class 102)	$85,000	$0.45	$0.34	$0.79
1,000,000	H13 8-cavity (Class 101)	$150,000	$0.30	$0.15	$0.45

The inflection point where injection molding becomes cheaper than CNC machining or 3D printing a similar ABS part is typically 500–2,000 units for simple geometries and 2,000–5,000 units for parts with side actions or tight tolerances.

Pro Tip

The inflection point where injection molding becomes cheaper than CNC or 3D printing is typically 500–2,000 units for simple geometries and 2,000–5,000 units for parts with side actions.

Section 6 of 8

Ten Ways to Reduce Injection Molding Costs

Split into design-phase and production-phase strategies - the earlier you optimize, the bigger the cost impact.

ADesign Optimizations

Eliminate undercuts

Redesign snap-fits, hooks, and internal features so the mold opens in a straight pull. Each side action saved removes $3,000–$8,000 from the mold.

Maintain uniform wall thickness

Target 1.5–2.5 mm for most resins. Core out thick sections. Every extra 0.5 mm adds ~5–10 seconds of cycle time.

Use generous draft

1–2° minimum on all vertical walls. More draft = faster ejection = shorter cycle.

Consolidate parts

If two parts snap together and are always assembled, consider molding them as one. You eliminate a mold, an assembly step, and an inventory SKU.

Use standard textures

MT-11000 series textures are stocked patterns - custom textures cost 2–3× more and have longer lead times.

BProduction Optimizations

Right-size the mold steel

Don't buy a Class 101 mold for 10,000 lifetime parts. A $5,000 aluminum prototype mold will serve you fine - and you can transition to steel later if volumes ramp.

Increase cavities at the right time

Moving from 1 to 2 cavities costs ~60% more for the mold but doubles output - amortized cost per part drops ~20% above 25,000 units.

Use hot runners for high volume

The $8,000–$15,000 hot-runner investment eliminates runner waste (10–30% material savings) and cuts cycle time by 2–5 seconds.

Negotiate resin pricing

Buying resin in bulk (pallet quantities, 2,000+ lb) typically saves 10–20% vs. small-lot pricing.

Optimize gate location

A well-placed gate fills the part uniformly, reduces weld lines, and eliminates cosmetic defects that require secondary operations (buffing, painting).

Pro Tip

The most impactful cost optimizations happen in the design phase. Wall thickness, undercut elimination, and draft angles are locked before tooling starts - get them right early.

Section 7 of 8

When to Use IM vs. Alternatives

Injection molding isn't always the answer. This table shows when alternatives (3D printing, CNC, urethane casting) are more cost-effective.

Volume	Best Process	Typical Per-Part Cost
1–10 parts	3D printing (FDM/SLS) or CNC machining	$15–$150
10–100 parts	CNC machining or urethane casting	$10–$80
100–1,000 parts	Prototype injection molding (aluminum tool)	$5–$50
1,000–10,000 parts	Production injection molding (P20 tool)	$1–$10
10,000+ parts	Production injection molding (H13 multi-cavity)	$0.30–$3

Bridge tooling strategy: For product launches with uncertain demand, start with an aluminum prototype mold ($3,000–$8,000). Produce the first 1,000–5,000 units to validate the market. If demand materializes, invest in production steel tooling with the revenue from initial sales.

Pro Tip

Use bridge tooling: start with a $3K–$8K aluminum mold for the first 1,000–5,000 units, then invest in steel tooling only after demand is proven.

Section 8 of 8

Hidden Costs to Budget For

These often-overlooked costs can add 10–25% to your program budget if not planned for upfront.

First-article inspection (FAI)

$500–$2,000 for a full dimensional report on the first shots. Required for medical and aerospace.

Engineering change orders (ECOs)

Modifying a hardened steel mold costs $1,000–$10,000 per change. Weld, re-machine, re-polish, re-texture. Get the design right before cutting steel.

Mold maintenance

Budget 1–3% of mold cost annually for cleaning, venting, and replacing worn components.

Mold storage

If you own the mold but it's stored at the molder's facility, expect $50–$200/month storage fees.

Secondary operations

Pad printing, hot stamping, ultrasonic welding, and insert molding all add $0.10–$2.00 per part.

Packaging and shipping

Molded parts are lightweight but bulky. Factor in custom trays or dunnage for cosmetic parts ($0.05–$0.50/part).

Pro Tip

Build a "hidden cost" line item into every injection molding program budget - plan for 10–15% contingency above the quoted tooling + part price.

Summary

Conclusion

Injection molding cost optimization starts in the design phase. The most impactful decisions - wall thickness, undercut elimination, mold steel class, and cavity count - are all determined before a single part is produced. Get these right and you'll have a cost structure that scales.

For programs with uncertain volume, use the bridge tooling strategy: aluminum prototype mold first, steel production mold when demand is proven. This de-risks the tooling investment while keeping your per-part cost competitive.

Aluminum Prototype Mold

Low Volume (100–1K)

Use a $2K–$10K aluminum tool (Class 105) for market validation and early production. Per-part cost is higher ($5–$50) but total investment is low.

P20/H13 Steel Tooling

Mid Volume (1K–50K)

Invest in production steel ($18K–$75K) once demand is proven. Per-part cost drops to $1–$3 and the mold lasts 100K–500K shots.

Multi-Cavity H13 Steel

High Volume (50K+)

Multi-cavity hardened steel ($50K–$200K+) delivers per-part costs under $1. Hot runners and optimized cycle time maximize ROI.

For programs with uncertain volume, use bridge tooling: aluminum prototype mold first, steel production mold when demand is proven. This de-risks tooling investment while keeping per-part cost competitive.

Common Questions

Frequently Asked Questions

How much does an injection mold cost?

Injection mold costs range from $2,000–$10,000 for aluminum prototype molds (Class 105) to $50,000–$200,000+ for hardened steel production molds (Class 101/102). The main cost drivers are part complexity, number of cavities, side actions, mold steel grade, and surface finish requirements.

What is the cost per part for injection molding?

Per-part cost depends heavily on volume. For a typical 30-gram ABS housing: ~$52.50/part at 100 units (tooling-dominated), ~$2.75/part at 10,000 units, and ~$0.45/part at 1,000,000 units. Material cost is usually 10–30% of total part cost at production volumes.

At what volume does injection molding become cost-effective?

The crossover point where injection molding becomes cheaper than CNC machining or 3D printing is typically 500–2,000 units for simple geometries and 2,000–5,000 units for parts with side actions or tight tolerances. Use bridge tooling (aluminum molds) for uncertain demand.

How can I reduce injection molding costs?

The top cost reduction strategies are: (1) eliminate undercuts to avoid side actions ($3K–$8K each), (2) maintain uniform wall thickness of 1.5–2.5 mm to reduce cycle time, (3) right-size your mold steel class to match lifetime volume, (4) use multi-cavity molds above 50,000 units, and (5) consolidate parts to eliminate extra molds and assembly steps.

What are the hidden costs in injection molding?

Common hidden costs include: first-article inspection ($500–$2,000), engineering change orders ($1,000–$10,000 per change on hardened steel), mold maintenance (1–3% of mold cost/year), mold storage ($50–$200/month), secondary operations ($0.10–$2.00/part), and custom packaging ($0.05–$0.50/part). Budget 10–15% contingency.

Should I use aluminum or steel tooling?

Aluminum molds ($2,000–$10,000, 500–5,000 shot life) are ideal for prototyping and market validation up to ~5,000 units. Steel molds ($8,000–$200,000+) are required for production volumes above 10,000 units. The bridge tooling strategy - start aluminum, graduate to steel - de-risks the investment.

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