Cost breakdown: material, conversion, tooling, finish, packing, freight

Why ask for a breakdown

A single piece price is enough to place an order and not enough to manage one. When the price changes, the buyer cannot see which line moved. When two suppliers differ, the buyer cannot see whether the difference is material, labour, tooling or margin.

A cost breakdown is a supplier's statement of how the price is built. It is not a guarantee of the supplier's internal costs, and it is not a should-cost model. It is a commercial document that can be compared, questioned and used as a baseline for a future change.

Some suppliers resist. They may treat the breakdown as confidential, or they may not have one. A supplier that cannot explain its price is still a supplier, but the buyer has less to work with when the market moves. Ask for the main lines, not the full internal ledger.

The request is easier to make at the quotation stage than after the order. State in the RFQ that a breakdown is required for the selected lines, and explain that it will be used as the baseline for volume and design changes. A supplier that knows the purpose is more likely to provide a usable document.

The material line

The material line should state the grade, the form, the input mass and the price basis. The input mass is the weight consumed per part, including the blank, the cut off, the runner or the machining allowance. The price basis should match the quantity the supplier buys and the delivery point.

Ask whether scrap is credited. A stamping that produces a skeleton or a machining operation that produces chips may recover some of the material value. If the credit is missing, the material line may be overstated. If it is included, ask for the recovery rate and the scrap value basis.

For a metal part, compare the material line with the published reference and the supplier's stated premium. Do not assume the reference is the purchase price. The premium, the form and the quantity explain part of the difference. The rest may be a buying assumption or a margin.

The conversion line

Conversion covers the machine time and labour to make the part. It usually includes the cycle time, the number of cavities or stations, the setup spread across the batch and the burden rate for the equipment.

Ask for the cycle time and the setup time separately. A low piece price can hide a long setup that is recovered through a minimum order quantity. A high piece price can reflect a slow cycle that is appropriate for a difficult feature. The number alone does not say which.

The burden rate is the least transparent part. It includes depreciation, space, power, maintenance and indirect labour. A supplier with new equipment may carry a higher rate but hold a tighter tolerance and a lower scrap rate. Compare the total cost, not the hourly rate on its own.

The tooling line

Tooling can be a one off charge, an amortised charge per part or a supplier funded cost recovered in the piece price. The breakdown should say which model applies, what the tool includes and whether the buyer owns it.

A one off tooling charge should come with its own breakdown: design, material, machining, assembly, tryout and transport. A single figure is harder to test. An amortised charge should state the total tool cost, the volume over which it is spread and what happens if the volume is not reached.

Check whether the tooling line is inside or outside the piece price. A quote that shows a low piece price and a separate tooling invoice may be cheaper or more expensive than a quote that folds the tool into the unit rate, depending on the volume. Put both on the same basis before comparing.

Finish, packing and freight

The finish line should name the process, the standard and the thickness or coating weight. Plating, passivation, powder coating and painting have different drivers. A plating line depends on surface area, barrel or rack loading, thickness and any masking. A coating line depends on coverage and cure.

Packing is often treated as a rounding item until a shipment arrives damaged. Ask for the carton, the divider, the unit count and the pallet configuration. If the part needs a clean room bag, a desiccant or a custom returnable, the cost belongs in the breakdown.

Freight should state the Incoterm, the mode, the origin and the destination. A freight line without a basis cannot be compared. If the supplier quotes DAP, ask for the freight and duty assumptions inside the price. If it quotes FOB, the buyer can apply its own freight rate.

The finish line also carries a quality cost. A plating thickness check, an adhesion test or a salt spray test may be charged separately or included in the unit price. Ask which tests are routine and which are extra, and put the acceptance criteria in the drawing or the purchase order.

Margin, payment and currency

Margin is a legitimate line. A supplier that shows no margin is either recovering it elsewhere or underpricing the work. Ask whether the margin is a percentage of the cost base or a fixed add, and whether it covers warranty, tooling risk and currency movement.

Payment terms change the price. A supplier that waits sixty days is financing the order, and that cost appears somewhere. A discount for earlier payment can be a useful test of how much the terms are worth. Compare the total cash cost, not only the piece price.

Currency is the third hidden line. A quote in one currency with costs in another carries a conversion assumption. Ask for the rate basis and the validity period, and check whether the breakdown uses the same rate as the quote.

The questions to ask

Use the table as a checklist for the first review. The goal is not to audit every number. It is to find the two or three lines that explain most of the price and to test the assumptions behind them.

Keeping the breakdown honest

Compare the breakdown with the drawing and the volume. A part with a tight tolerance but a very low conversion time is a contradiction worth checking. A material line that is below the market reference is either a buying advantage or an error, and the answer matters.

Keep the accepted breakdown with the purchase order. When the supplier asks for an increase, ask which line moved and for the evidence. When the design changes, ask for the affected lines only. A baseline turns a price discussion into a comparison against a known starting point.

Review the breakdown when the volume, the material, the tooling or the route changes. A breakdown is a snapshot of assumptions. It stays useful only if it is updated when the assumptions do.

A final check is to compare the breakdown with the physical part. The material grade, the finish and the packed weight can be checked against the drawing and a sample. A line that does not match the part is a question, even when the total price looks acceptable.

• Tie every line to a driver and a unit.
• Ask for the input weight and the scrap credit.
• Separate setup from cycle time.
• Confirm whether tooling is inside or outside the piece price.
• State the freight basis and the Incoterm.
• Record the accepted breakdown with the order.