Powder Coating Cost: What Sets the Price
Powder coating is usually the most economical durable finish for sheet metal, and it is also the finish most often quoted as a single blended number. Understanding which of its five cost elements is actually driving your price tells you whether a specification change or a batching change is the right lever.
Powder coating is priced by surface area, pretreatment, colour and batch minimum, film thickness and masking. Pretreatment is the variable buyers miss: a part that needs a conversion coating before powder costs more to prepare than to coat, and a bespoke colour carries a batch minimum a standard RAL does not.
5 rows of reference data below — the summary above is the short answer, the tables are what you quote from.
The five elements of a coating price
| Element | Driver | How it is reduced |
|---|---|---|
| Surface area | Total area to be coated, both faces or one | Mask by design so unmasked area is genuinely functional |
| Pretreatment | Substrate and required adhesion class — degrease, phosphate, chromate conversion | Choose the substrate that needs the lightest adequate pretreatment |
| Colour and batch minimum | Standard RAL versus matched colour; whether a dedicated batch is needed | Consolidate parts to one standard RAL per run |
| Film thickness | Specified range; thicker films consume more powder and time | Specify the range the environment needs, not the maximum available |
| Masking and handling | Threads, mating faces, earth points, high-visibility surfaces | Design the part so fewer features need masking |
Powder coating cost elements
Pretreatment is the element that is not really about coating
Powder adheres by mechanical and chemical bonding to a prepared surface. On bare cold-rolled steel that means degreasing and a phosphate layer. On galvanised or zinc-coated steel it means a different pretreatment chemistry, because the zinc surface behaves differently from steel and the wrong sequence produces blistering or poor adhesion that appears months later rather than at inspection.
This is why a galvanised enclosure and a bare-steel enclosure of the same size can carry noticeably different coating costs. The cost difference is not in the powder; it is in the chemistry and the number of process stages before the powder is applied.
Why batch minimums exist, and how to use them
A coating line is a sequence of stages — clean, rinse, conversion, dry-off, spray, cure — and a colour change means clearing the booth and the recovery system. Setting up for a bespoke matched colour, or for a colour that has not run recently, costs the same whether the batch is ten parts or a thousand.
The practical consequence is that batching beats splitting. If three panel types will all be the same RAL 9005 satin, running them as one batch shares the setup and the minimum. If the same parts need three different bespoke colours, three minimums apply, and the honest design advice is often to standardise on fewer colours.
Where powder coating is the wrong choice
- Threads and close-tolerance bores: the film builds 60–120 µm per face and will change the fit unless masked or tapped after coating.Grounding and electrical contact faces: a cured powder film is an insulator, and every earth path has to be masked and verified.Moving interfaces — hinges, slides, mating machined faces — where the film thickness changes the clearance.
- Very large flat cosmetic panels where a thin film and a smooth finish matter more than impact resistance; a wet paint may match better.Aluminium parts where the customer wants the metallic anodised appearance; coating hides the substrate rather than enhancing it.
What to put on the drawing
- Colour to a reference standard — a RAL or Pantone number, with the finish type (gloss, satin, matt, textured).Film thickness range, if the environment or a specification requires one.Which faces are cosmetic, and which faces may be coated freely.
- Explicit masking instructions for threads, bores, earth points and mating faces.The pretreatment expectation where the substrate demands a specific conversion coating.
Frequently asked questions
Is powder coating priced per part or per square metre?
Effectively per square metre of coated area plus a fixed batch element. Two parts with the same area can still differ in price if one needs a heavier pretreatment or more masking, which is why the area alone does not determine the number.
Why does a bespoke colour cost more than a standard RAL?
Because a matched colour has to be made up and the line set up for it specifically, and that setup cost is the same for a small batch as a large one. A standard RAL that is already in the schedule shares setup with other work.
Does powder coating protect cut edges?
It covers them, but a coating is a barrier rather than a sacrificial layer, and a cut edge is where a barrier fails first under impact. On steel, a zinc-coated substrate beneath the powder gives the sheared edges sacrificial protection that a coating over bare steel cannot.
How thick is a powder coat, and does it matter?
Typically 60–120 µm per applied face, depending on the product and the specification. It matters wherever a dimension is functional: a masked thread, a gasket groove, a press fit, or an earth stud. Tell us those features and we will mask them.
Can you match an existing painted part?
Usually yes, from a physical sample or a colour reference. Send the part or the RAL code and we will confirm what is achievable and whether a bespoke batch is required, since that decision changes both the price and the lead time.
Send the drawing, get a real answer
An engineer reviews your model for manufacturability and returns a costed quotation — with the DFM observations that would change the price.