Last quarter, my team was designing a portable Bluetooth speaker for a client. The speaker needed to be slim (under 3cm thick) and durable enough to handle drops. We had two options for the PCB: a traditional rigid PCB (which we’d used for past projects) or a rigid-flex PCB (which could bend around the battery to save space). But there was a catch: the client’s budget was tight—we couldn’t spend more than $2 per unit on PCBs.
“We need to run the numbers,” our cost engineer, Mia, said, pulling up a spreadsheet. “Rigid-flex sounds great for space, but if it’s too expensive, we’ll have to stick with traditional.” Over the next three days, we broke down every material cost—from 基材 to adhesives to processing. What we found surprised us: rigid-flex wasn’t as expensive as we thought, and in some cases, it even saved money.
This experience taught us that choosing between rigid-flex and traditional PCBs isn’t just about “functionality”—it’s about understanding how material costs add up. Traditional PCBs seem cheaper at first glance, but rigid-flex can eliminate extra costs (like wires or connectors) that sneak up on you.
In this article, we’ll break down the material costs of both PCB types, compare them side-by-side, and share when rigid-flex is worth the investment (and when traditional is better for your budget).
Before we compare, let’s clarify what “material costs” include—because it’s more than just the base board. For both rigid-flex and traditional PCBs, costs fall into four key categories:
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Traditional PCB: Uses FR4 (a fiberglass-reinforced epoxy resin), the most common and cheapest substrate. A standard 1.6mm-thick FR4 sheet costs $0.50–$1.00 per square inch.
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Rigid-Flex PCB: Uses two substrates: FR4 for rigid sections (same as traditional) and PI (polyimide) film for flexible sections. PI is more expensive—$1.50–$3.00 per square inch—because it’s thinner, more durable, and heat-resistant.
“PI is the biggest cost jump for rigid-flex,” Mia said. “But you only use it for the flexible parts—you still use FR4 for the rigid sections, so you don’t pay for PI everywhere.”
Both PCBs use copper for signal traces, but rigid-flex often needs thinner, more precise copper (to fit in tight spaces):
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Traditional PCB: Uses 1oz–2oz copper (thicker, easier to manufacture). Cost: $0.10–$0.20 per square inch.
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Rigid-Flex PCB: Often uses 0.5oz–1oz copper (thinner, for flexibility). Thinner copper is slightly more expensive ($0.15–$0.25 per square inch) because it requires more precise manufacturing.
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Traditional PCB: If it’s multi-layered, it uses standard epoxy adhesives to bond layers. Cost: $0.05–$0.10 per square inch.
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Rigid-Flex PCB: Needs special adhesives to bond FR4 and PI (they have different heat expansion rates). These adhesives (like acrylic-based ones) cost more—$0.15–$0.25 per square inch—but prevent the PCB from splitting when bent.
This is where traditional PCBs often hide extra costs:
Let’s use our Bluetooth speaker project as an example. The speaker needed a PCB with:
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2 square inches of total area (1.5 square inches rigid, 0.5 square inches flexible for rigid-flex).
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1oz copper traces.
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2 layers.
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Connections between the display, battery, and speaker driver.
Here’s how the costs stacked up:
At first glance, rigid-flex was more expensive—$0.465 per unit. But here’s the catch: the traditional PCB design forced us to make the speaker 3.5cm thick (too thick for the client’s request), while the rigid-flex design let us hit the 3cm target. “We either paid $0.465 more per PCB or lost the client,” Mia said. “It was an easy choice.”
Rigid-flex’s higher upfront material costs don’t always mean a higher total cost. Here are three scenarios where rigid-flex actually saves money:
Traditional PCBs often require extra wires or connectors to link multiple boards. These add not just material costs, but also assembly time (which costs money) and failure risks (which cost more to fix).
“We had a smartwatch project where traditional PCBs needed 3 wires and 2 connectors—$0.70 per unit in extra materials, plus 2 minutes more assembly time ($0.20 per unit),” Mia said. “Rigid-flex skipped all that—total savings: $0.90 per unit, even though the PCB itself was $0.30 more expensive.”
If a traditional PCB forces you to make your product bigger (e.g., a thicker phone, a bulkier sensor), you’ll pay more for other components: a bigger battery, a larger casing, more packaging.
Our Bluetooth speaker is a perfect example: the traditional PCB needed a 10% bigger battery (to fit the thicker design) which cost $0.30 more per unit. Adding that to the traditional PCB’s $2.46 cost made it $2.76—only $0.165 cheaper than rigid-flex. “The ‘cheaper’ PCB actually made other parts more expensive,” Mia said.
Rigid-flex is more durable than traditional PCBs (it resists bending, vibration, and drops). This means fewer failed units, fewer repairs, and fewer recalls—all of which save money long-term.
“A client had a industrial sensor project where traditional PCBs failed at 5% rate (costing $10 per failed unit to fix),” said our sales manager, Raj. “Rigid-flex failed at 0.5% rate—saving $4.75 per unit in repair costs. That more than covered the $0.60 higher PCB cost.”
Rigid-flex isn’t always the best choice. Here are two scenarios where traditional PCBs are cheaper and more practical:
If your product is flat (e.g., a basic TV remote, a simple LED light) and only needs one PCB, traditional FR4 is cheaper. You don’t need the flexibility of rigid-flex, so you’re just paying extra for features you won’t use.
“We use traditional PCBs for our basic remote controls—they’re flat, need one board, and no wires,” Raj said. “Cost: $1.20 per unit vs. $1.80 for rigid-flex. No reason to pay more.”
Rigid-flex requires specialized manufacturing (to bond FR4 and PI), which has higher setup costs. For small production runs (under 1,000 units), these setup costs make rigid-flex much more expensive.
“If you’re making 500 units of a prototype, rigid-flex setup costs ($500) add $1 per unit,” Mia said. “Traditional PCBs have $100 setup costs—only $0.20 per unit. For small runs, traditional is better.”
A headphone company had to choose between traditional and rigid-flex PCBs for their wireless earbuds. Here’s what happened:
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Small size (earbud-sized PCB).
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Connections between the battery, speaker, and touch sensor.
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Production run: 10,000 units.
Rigid-flex was $0.30 cheaper per unit—because it skipped wires and reduced assembly time. The company saved $3,000 total on 10,000 units and made the earbuds 15% smaller. “We thought rigid-flex would be more expensive, but it ended up saving us money,” said the company’s engineer.
Our Bluetooth speaker project taught us that comparing rigid-flex and traditional PCBs by material cost alone is a mistake. You need to look at the total cost: PCB materials, extra components (wires, connectors), assembly time, and long-term durability.
Rigid-flex may have higher upfront material costs, but it often saves money by eliminating extra parts, fitting into smaller designs, and reducing failures. Traditional PCBs are cheaper for simple, flat, low-volume projects—but they can cost more in the long run for complex, space-sensitive products.
Next time you’re choosing between the two, ask: “What will this PCB cost me in total—not just to buy, but to build into my product?” The answer might surprise you. Sometimes, the “more expensive” PCB is actually the cheaper choice.
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