Two quotes for the same machined part come back far apart. The lower one is rarely a mistake and rarely a bargain. It usually contains less: one fewer finishing step, a substituted material assumption, a tolerance nobody priced, or an inspection report that was never in scope. Compare the totals and you are comparing two different products.
We are a sourcing and freight team in Shenzhen, not a machine shop. Since 2019 we have reviewed these quotes for 4,000+ buyers shipping to 200+ countries. We show the factory invoice separately from our own fee, so the exercise below is the one we run with a buyer before any deposit moves.
- Send every supplier the same complete RFQ pack, or the quotes are not comparable at all.
- Ask for an itemised quote with nine named lines, not a single unit price.
- Do not compare machine hourly rates; compare the fully loaded, per-part price.
- Find the hidden costs before the purchase order, while they are still questions rather than change orders.
- Request quantity tiers in one request, because the process itself changes with volume.
- Judge the number on landed cost, not on the ex-works line.
What actually drives a machining quote
Buyers often assume a quote is mostly material plus machine time. Those two matter, but on a precision part the setup, inspection and finishing decisions frequently decide the total. Here is what a shop is really pricing.
| Cost driver | How it moves the number | What to confirm |
|---|---|---|
| Material grade and stock form | Special grades, unusual thicknesses and poor nesting waste expensive stock | Exact grade and condition, and whether offcuts are usable |
| Cycle time and number of setups | Every re-fixturing adds labour, risk and machine time | How many setups, and whether a fifth axis removes one |
| Programming and fixturing | One-off engineering spread over the order quantity | Whether it is a separate NRE line or buried in the unit price |
| Cutting tools and consumables | Hard materials, deep pockets and small tools wear cutters faster | Who bears tool replacement on a long run |
| Tolerance and inspection burden | Tighter features require slower finishing, more measuring and more scrap | Which dimensions are critical, and what report is included |
| Surface finish and subcontracted steps | Anodising, plating, heat treatment and passivation often leave the building | Who owns the part in transit and who pays if the finish fails |
| Quantity and amortisation | Setup cost per part collapses as volume rises | Quotes at several quantity breaks, not one |
| Packaging and inland freight | Protective packing for finished faces and transport to the consolidation point | Whether the quote is ex-works, to a warehouse, or to a port |
Two suppliers can be equally efficient and still return very different totals if one has assumed a single setup and the other has assumed three. That is a quoting assumption, not a performance difference, and it is exactly what an itemised quote exposes.
The nine lines a comparable quote should show
We ask for the following split, in writing, before comparing suppliers. If a shop will not provide it, we treat the quote as indicative rather than comparable.
- Raw material, with grade, condition and stock form named.
- Machine time, or a stated cycle-time assumption per part.
- Programming, setup and fixturing as one-off lines.
- Tools, electrodes or consumables where the geometry makes them significant.
- Subcontracted processes, each named separately.
- Inspection and reporting, including first article and any dimensional report.
- Protective packaging appropriate to the finish.
- Inland freight to the named hand-over point.
- One-off tooling or NRE, never blended silently into the piece price.
Then ask who owns each of those one-off items. A fixture, a program or a die that you paid for but cannot take with you is a cost you may pay twice. Our tooling ownership guide covers the stamped-part version of that problem.
Hourly rate is the wrong number to compare
“CNC machining cost per hour” is the most searched version of this question and the least useful. A low hourly rate multiplied across extra setups, a conservative cutting strategy and a higher scrap allowance can produce a more expensive part than a higher rate from a shop that holds the tolerance first time. The rate says nothing about how many hours your part consumes.
Ask instead for a fully loaded per-part price at a stated quantity, plus the itemised breakdown above, and ask one technical question: how many setups does this part need? A supplier who answers that concretely has actually read the drawing. A supplier who only defends the hourly rate has not.
This is also where an incomplete RFQ does the most damage. If the drawing does not state material condition, thread class, surface finish per feature or inspection requirement, each shop fills the gaps with its own assumption. The full file list is in our sourcing checklist, and our note on general tolerances explains why vague drawing notes are a cost driver in their own right.
Where the hidden costs sit
A quote is not expensive when it includes everything. It is expensive when the missing items reappear later as a change order, a re-make or an air freight bill. These are the omissions we look for first.
| Common omission | How it reappears | Ask before the purchase order |
|---|---|---|
| Deburring and edge breaking | A per-part surcharge, or parts rejected at goods-in | Is edge treatment included, and to what standard? |
| Surface finish or passivation | A separate subcontractor invoice after machining | Name each finish and its acceptance criteria |
| Dimensional and material reports | Charged as an extra when the buyer asks for evidence | Specify the report in the RFQ, not afterwards |
| Protective packaging | Scratched cosmetic faces on arrival | Ask how finished faces are separated and protected |
| Inland freight and export handling | A gap between the factory gate and the port | State the hand-over point and the Incoterm |
| Engineering changes | An open-ended revision fee mid-project | Agree how an ECN is quoted and approved |
| Raw material price adjustment | A revised unit price after the order is placed | Ask whether the quote is firm and for how long |
None of these are dishonest on their own. They only become expensive because they were never in the comparison. A quote that is somewhat higher and includes them is usually the cheaper contract.
Quantity tiers change the answer
Ask for 1, 10, 100 and 1,000 pieces in a single request, with one-off setup and tooling shown separately. The shape of that curve tells you more than any unit price: you can see where setup stops dominating, and where a supplier quietly changes the assumed process.
That second point matters. At prototype quantity a part is milled from billet; at volume the same geometry may be stamped, cast or formed, with tooling amortised across the run. Our process comparison explains how to find that crossing point. Do not take a prototype unit price into a volume negotiation, and do not accept a volume price that assumes a process you have not approved.
Compare on landed cost, not ex-works price
The ex-works line is one component of what you will actually pay. Duty treatment depends on HTS classification and origin, and the freight choice depends on the packed weight and dimensions of dense metal parts. A slightly higher factory price shipped under a well-documented DDP arrangement can beat a cheaper ex-works quote once duties, clearance, inland transport and consolidation are counted.
Our landed cost guide sets out the full worksheet, and the consolidation guide covers what happens when machined, stamped and finished parts come from different workshops. Ask your licensed customs broker to confirm classification before you treat any two quotes as comparable.
A one-pass quote review
When we review a set of quotes for a buyer, we do four things: normalise the RFQ so every supplier quoted the same scope, mark the missing lines, ask each shop to confirm its setup and process assumptions in writing, and rebuild the comparison on landed cost. We also verify the entity behind the quote before anyone pays a deposit, using the checks in our supplier verification guide.
Because we are not the factory, there is no reason for us to defend a particular number. We show the factory invoice separately from our own fee, and if the honest answer is that a different process or a different workshop is cheaper, that is the answer we give. The full scope of that role is described in what a sourcing agent actually does.
Frequently asked questions
How much does CNC machining cost per hour in China?
There is no useful single figure, and the hourly rate is a poor comparison anyway. What matters is the fully loaded per-part price at your quantity: cycle time, number of setups, tooling, finishing, inspection and scrap allowance. Ask two or three qualified shops to itemise the same specification and compare the structure of their quotes rather than a rate card.
Why is one Chinese supplier’s quote so much cheaper than the others?
Usually because something is outside the scope: a finishing step, a material assumption, a tolerance nobody priced, inspection, protective packaging or inland freight. Ask for an itemised quote and a written list of exclusions. Sometimes the cheaper quote is genuinely more efficient, but you cannot tell until the scope matches.
Should tooling and NRE be quoted separately from the unit price?
Yes. A separate one-off line lets you see how setup amortises across quantity tiers and makes ownership of fixtures, programs and dies explicit. When tooling is blended into the piece price, both the crossover point and your claim to the tool become harder to establish.
Does a lower unit price always mean a lower landed cost?
No. Duties, classification, inland freight, export handling, consolidation and the chosen Incoterm all sit between the factory price and your door. A quote that is slightly higher ex-works but includes documentation and door-to-door delivery can be cheaper in total. Compare landed cost, with classification confirmed by a licensed broker.
How do I compare quotes from three Chinese suppliers fairly?
Send all three the same RFQ pack and the same quantity breaks, require the same nine itemised lines, ask each to state its process and setup assumptions, then rebuild the comparison on landed cost including inspection, packaging, freight and duties. Reject quotes that will not disclose exclusions.
Send us two or three quotes you are comparing, with the drawing and your target quantity. We will normalise the scope, mark the missing lines and come back within 24 hours with a comparison you can audit line by line. Send your quotes and we will start with the exclusions.