Send the same cable drawing to five suppliers and you will get five prices. Sometimes the spread is a few percent. Sometimes it is forty, and the drawing never changed.
The instinct is to assume the high quote is padded or the low one is cutting corners. Sometimes one of those is true. More often, both suppliers priced the same words and made different assumptions about what those words required. The gap is not in the price. It is in the scope.
Here are the places that gap opens, in rough order of how much money sits in each one.
Start with the metal, because the metal moves on its own
Copper is the dominant cost driver in wire and cable pricing, and how dominant depends entirely on the cable. One US distributor’s published explanation puts the copper conductor at anywhere from 10 percent to over 80 percent of total material cost, depending on cable size and complexity, and notes that a large 750 MCM power cable carries a far higher copper share by weight than a small shielded multi-conductor cable. Insulation and jacket compounds cost far less per unit, and the smaller and more complex the cable, the larger the share taken by shielding, fillers and assembly labor.
A separate industry piece states that copper constitutes 60 to 70 percent of the total cost of most cables. That figure and the 10-to-80 percent range are not reconcilable as written — one is expressed against material cost, the other against total cost, and neither source defines its denominator. Treat both as directional, and ask your supplier to state the copper basis on the quote rather than inferring it.
What is not in dispute is that the metal moves quickly. The US Bureau of Labor Statistics publishes a producer price index for copper wire and cable, available through the Federal Reserve’s FRED database. Across five months of 2026 it moved like this:
Month 2026 | Index value (Dec 1986 = 100) |
|---|
April | 533.808 |
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May | 564.877 |
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June | 577.166 |
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July | 578.187 |
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August | 602.480 |
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That is a rise of about 12.9 percent in five months, computed from the published index values. Manufacturers respond on that timescale. One distributor describes wholesale prices being adjusted on a monthly, weekly and even daily basis, with at least one manufacturer updating twice in the same day during a copper spike. Larger producers hedge copper purchases to lock prices in; others sell on tiered pricing adjusted periodically against copper market indexes.
A quote with no stated basis and no validity date is not comparable to anything.

Diagram showing that the copper conductor dominates material cost in large power cable and takes a smaller share in small complex shielded cable
The seven places two quotes diverge

The seven cost levers grouped into metal price, scope and specification, and commercial terms
1. The copper basis, and the date it was valid
Two quotes can both be honest and 12 percent apart because one was priced against April copper and the other against August. Ask for the basis — a named exchange, a named index, or a fixed number — the date it was taken, and how long the quote stands. If a supplier offers a copper adjustment clause instead of a fixed price, that is not a trick. It is the industry’s normal answer to volatility, and it shifts the risk of the metal moving to you. What matters is that every quote you compare uses the same mechanism, so you are comparing scope rather than risk appetite.
2. Material take-off: nominal or minimum
A specification usually sets a nominal dimension and a floor beneath it. A US federal cable specification, for example, requires minimum jacket thickness to be no less than 80 percent of nominal. A supplier engineering to nominal and a supplier engineering to 80 percent both meet that specification, and they do not consume the same quantity of compound per meter. On a large order the difference is real money, and it is invisible on the quotation unless you ask which wall thickness was priced.
3. Whose catalog the diameter is measured against
Diameter limits are usually written against a reference rather than an absolute. The same federal specification allows no more than 5 percent variation for single-conductor cable and 10 percent for multiple-conductor cable, measured from the manufacturer’s published catalog data. Read that carefully: the tolerance is not against a dimension on your drawing. It is against whatever the manufacturer chooses to publish. Two suppliers can both comply while shipping measurably different diameters. If the cable must pass a gland, a conduit or a connector entry with a fixed opening, put the absolute dimension on the drawing and accept that you are buying a tighter process.
4. The acceptance class, and who absorbs rework
Workmanship standards are class-based, and the class is a cost decision. Under IPC/WHMA-A-620 the buyer identifies the acceptance class, and if the buyer does not establish and document it, the manufacturer may choose it. That one sentence sets how much inspection and rework a supplier prices into the job. The same standard states plainly that no limit is placed on the number of process indicators or the number of allowable repair or rework of defects. A supplier pricing Class 3 assembly labor and a supplier pricing an end-of-line electrical test are quoting two different factories for one drawing.
5. Test and certification scope
Test scope is the difference between a cable and a certified cable. HDMI’s Ultra High Speed program is mandatory, and every length of every model must pass testing at an Authorized Test Center before the certification label can be applied — and that cost recurs, because the program requires continuing audit testing of cables already on the market. Factory testing works the same way: a specification can require inspection and tests to be made at the manufacturer’s plant and witnessed unless waived in writing. If one quote includes certification and the other assumes you will arrange and pay for it, the two prices describe different deliverables.
6. Order quantity and the one-time costs inside it
Cable carries one-time costs that must be recovered across the run: extrusion tooling, a connector mold, a printing plate for jacket marking, and the setup scrap produced at the start of every production block. Spread across 50,000 meters those are rounding errors. Spread across 500, they are the quotation. This is where minimum order quantities come from — not from supplier policy, but from the arithmetic of setup. If the cheaper quote carries a much larger minimum, you may be looking at the same total cost distributed differently.
7. Packaging, freight basis and who keeps the drum
Packaging changes material cost and freight together. A wooden drum, a coil and a box hold different lengths and weigh different amounts, and drums are not always sold with the cable: the same federal specification states that reels remain the property of one of the contracting parties. Freight terms move the number further. An FOB quote and a delivered-duty-paid quote differ by freight, insurance and duty, and cable is dense and heavy enough that those lines are not small. Never compare two quotes on different Incoterms without converting them to the same one.
The like-for-like page to send every supplier
None of this needs a cost model. It needs one page with the same questions on it, sent to everyone quoting.
Question to ask | Why it changes the price |
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What copper basis and date was used, and how long does the quote stand? | Same drawing, different metal price |
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What jacket and insulation wall thickness was priced, nominal or minimum? | Different compound consumption per meter |
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Is the diameter measured against your published catalog or an absolute drawing dimension? | Compliant cables, different physical sizes |
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Which acceptance class was priced, and who chose it? | Different inspection and rework load |
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What exactly is tested, and by whom, and is any certification included? | Test and certification are separate deliverable lines |
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What is the minimum order quantity, and what one-time cost drives it? | Setup and tooling recovered differently |
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What packaging is included, and who owns the drum afterwards? | Material cost plus return or disposal cost |
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Which Incoterm is quoted, and what is excluded? | Freight, insurance and duty placement |
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What documentation ships with the goods? | Traceability and release paperwork |
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What is the production lead time, and what does expediting cost? | Capacity, not material |
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A quotation is comparable to another quotation only when both are priced against the same revision, the same class, the same test scope, the same packaging and the same copper basis. Everything else is a comparison of two different projects.

Line chart of the US producer price index for copper wire and cable from April to August 2026, rising from 533.808 to 602.480
FAQ
Why is my cable quote higher than the one I got last quarter?
Most likely the metal. The US producer price index for copper wire and cable rose from 533.808 in April 2026 to 602.480 in August 2026, about 12.9 percent, computed from the published values. Manufacturers commonly reprice against copper on a monthly or weekly cycle, so a quote from last quarter may simply be an older metal price.
What is a copper price adjustment clause?
An agreement that the price follows a named copper index instead of being fixed at order. It is common practice in the cable trade, and its effect is to move the risk of copper movement from the supplier to the buyer. Ask which index, which reference date and how often it is applied, then compare all suppliers on the same basis.
Why is there a minimum order quantity?
Because of setup costs that do not scale: tooling, dies, printing plates and the scrap produced while a line comes up to specification. The minimum exists to spread those costs over enough meters that the price per meter stays sane. A longer run is usually cheaper per meter for that reason alone.
Does a lower price mean lower quality?
Not automatically, and not the other way around either. What it usually means is a different scope: a thinner wall, a wider diameter allowance, less inspection, no certification, a different freight basis or a larger minimum. Ask the questions on the comparison page, and the reason for the difference normally becomes visible.
Conclusion
Two prices for one drawing differ for reasons that are almost always findable. The metal moved. The wall thickness was engineered to the floor rather than the nominal. The diameter was measured against a catalog rather than a drawing. The acceptance class was chosen by whoever stayed quiet. Certification was assumed to be someone else’s cost. The setup cost was spread over a different quantity. The Incoterm was left implicit.
None of those are dishonest. All of them are invisible until you ask, and every one of them is cheaper to resolve before the order than after it.
Comparing quotes with ZONG Cable
ZONG Cable quotes cable and cable assemblies with the copper basis, the validity window, the acceptance class, the test scope and the Incoterm stated on the quotation rather than left for you to work out. If you are holding two or three quotes for the same drawing and want to know where the difference actually sits, send them over with the drawing and we will line the assumptions up side by side — including when the conclusion is that someone else’s price is the honest one for what you asked for. Our OEM support page covers how drawings and quantities are quoted, the electrical and dimensional routines behind each shipment are on our test and inspection page, and the range sits under cable.
Sources
- Producer Price Index by Commodity: Metals and Metal Products: Copper Wire and Cable [WPU10260314], U.S. Bureau of Labor Statistics, retrieved from FRED, Federal Reserve Bank of St. Louis. https://fred.stlouisfed.org/series/WPU10260314
- How Will Copper Tariffs Affect Wire and Cable Prices?, Pro Wire and Cable. https://prowireandcable.com/pro-wire-and-cable-blog/how-will-copper-tariffs-affect-wire-and-cable-prices/
- How Rising Copper Prices Are Impacting the Cable Industry, Polycab News. https://polycabnews.com/industry-news/how-rising-copper-prices-are-impacting-the-cable-industry/
- UFGS-26 05 19.00 10, INSULATED WIRE AND CABLE, Unified Facilities Guide Specifications, USACE / NAVFAC / AFCEC, February 2026. https://legacy.wbdg.org/FFC/DOD/UFGS/UFGS%2026%2005%2019.00%2010.pdf
- IPC/WHMA-A-620F table of contents and front matter, Global Electronics Association. https://www.electronics.org/TOC/IPC-WHMA-A-620F-TOC.pdf
- New Ultra High Speed HDMI Cable Certification Program, HDMI Forum, Inc. https://hdmiforum.org/new-ultra-high-speed-hdmi-cable-certification-program-assures-support-for-all-hdmi-2-1-features-including-8k/
- ZONG Cable OEM support. https://zh-zong.com/oem-support/