Polycarbonate vs Acrylic Sheets: A Cost Controller’s 5-Point Comparison

Polycarbonate vs acrylic sheets: five things I actually compare

I’ve signed off on roughly $2.1 million in plastic sheet, packaging, and shop consumables over the past six years. I run procurement for a 140-person fabrication shop, I’ve negotiated with 11 sheet suppliers, and every order goes into a cost tracker I built after getting burned twice on charges that weren’t on the quote.

The comparison I get pulled into most often is polycarbonate vs acrylic sheets. Usually a project manager is holding two quotes that differ by 2.5x and asking which one is “right.”

The honest answer is that neither is right in the abstract. It depends on five things, and only one of them is the number on the quote:

1. What you pay per usable finished part (not per sheet)
2. How long the clarity actually holds
3. What happens when it gets hit, or gets hot
4. How much you scrap getting it into shape
5. Everything on the PO that isn’t the sheet

I’ll give a verdict on each. One of them came out the opposite of what I assumed when I started tracking, and it’s the one that costs the most money.

1. Sticker price: acrylic wins, and it matters less than you think

On our Q4 2024 purchase orders, 3mm clear acrylic at 4x8 ft ran $58 to $74 a sheet depending on brand, masking, and whether we took a full pallet. 3mm clear polycarbonate at the same size: $132 to $168. That’s 2.2x to 2.8x, and I’m not going to pretend that gap doesn’t matter — on a 200-sheet job it’s five figures.

But per-sheet price is the wrong denominator. What we actually track is cost per compliant finished part, and that number moves for reasons that have nothing to do with the sheet price.

Concrete example from last spring. We bid a run of 480 formed covers. Acrylic sheet ran us $61 each; PC was $149. Sounds like a no-brainer for acrylic until we added scrap: we broke 7% of the acrylic during forming and trimming, versus under 1% of the PC. Plus the acrylic parts needed a slower forming cycle, which ate about 14% more press time on a run we’d already quoted.

Cost per good part landed within 6% of each other. The “cheap” material was still cheaper, but nowhere near the margin the quotes implied. Bottom line: use sheet price to decide what to quote, and finished-part cost to decide what to buy. Those are two different spreadsheets, and mixing them up is how projects get quietly unprofitable.

2. Optical clarity and UV: acrylic, clearly

If the part is visible to a customer — signage, display, window, a viewing panel on a machine — this is usually the decision-maker.

Acrylic transmits about 92% of visible light at 3mm; polycarbonate sits around 88–90%. (Those are the numbers on the datasheets we keep on file, and honestly, don’t hold me to the decimal — grade, tint, and coating all move them. ASTM D1003 is the test method you want your supplier quoting, if they quote one at all.)

The bigger difference shows up over time. Acrylic is inherently more UV-stable. Polycarbonate yellows in sunlight, and the standard fix is a hard coat that blocks UV — which works, right up until someone cleans it with the wrong solvent or scratches through it, and then you get a yellow patch exactly where the damage is. That’s a warranty conversation you do not want.

Which is also why I ask what’s behind the claim. If a datasheet says “UV-resistant” with no test method, that’s an unsubstantiated statement — FTC guidance (ftc.gov) is fairly clear that advertising claims need evidence behind them, and in my experience vendors produce actual documentation pretty fast once you ask.

So for anything outdoors or under bright light for five-plus years, I default to acrylic unless impact is the primary risk. That’s not a compromise, it’s the right call.

3. Impact and heat: polycarbonate, and it’s not close

This is where the counterintuitive part starts.

Polycarbonate is commonly quoted at roughly 30 times the impact strength of acrylic at the same thickness (Izod impact, ASTM D256, is the number you’ll see on datasheets). It also holds usable strength at temperatures where acrylic has already gone soft. Acrylic’s heat deflection point sits around 90–100°C depending on grade and load; PC keeps working well above that.

Here’s what that means in dollars. In 2023 we replaced a run of acrylic machine guards that had cracked within eight months — three separate sheets, all failing at the mounting holes. Not a supplier problem. Acrylic just doesn’t like point loads and vibration, and guards get both. We swapped to 6mm PC at roughly $310 a sheet against $96 for the acrylic, and none of the replacements have cracked in 18 months.

If the part is a safety shield, a guard, a visor, a lens, or anything a forklift might bump into, buy polycarbonate. That’s a deal-breaker, not a preference.

4. Fabrication and scrap: closer than the price gap suggests

Neither material is “easy,” they’re just difficult in different ways.

Acrylic chips and crazes. Drill it too fast and you get star cracks around the hole that turn into full failures later — a slow-burn defect, which is worse than an obvious one because it ships. On the other hand, acrylic solvent-cements beautifully, which is a real advantage if you’re building a box or a display.

Polycarbonate gums. A jigsaw will melt and re-weld behind the blade if your feed rate is wrong, and then you’re sanding a mess. Sharp PC-specific tooling and slower speeds fix it — but your shop has to actually change setups, and setups are what people skip when they’re behind schedule.

In our shop the scrap rate runs about 4% on acrylic and roughly 1% on PC across comparable jobs, mostly from breakage in handling and trimming. That’s the number that quietly eats the acrylic savings, and nobody puts it in the quote comparison because it doesn’t show up until month two.

5. Everything that isn’t the sheet

This is the dimension I got wrong for two years, and it’s the one I’d tell anyone to check first.

The sheet is maybe 70% of the landed cost of a plastic panel job. The rest lives in items that never appear on the sheet quote, and that’s where the real money leaks.

Interleaving and packaging. If you buy PE foam for interleaving between finished panels, buy the thickness you actually need — 2mm closed-cell does the job for most flat parts, and going to 4mm “for safety” adds real cost across a year. We were buying PE foam through our sheet supplier at roughly 40% over what a direct foam distributor quoted for the same spec. That was $6,800 a year for zero benefit. Nobody caught it because it was four lines down on the PO.

PTFE strip. We use PTFE strip as a release surface on our heat-sealing bars and at the die station. It’s an inexpensive item, which is exactly why nobody watches it. We were reordering 12mm × 5m rolls at $34 when a 25m roll at $96 was available from the same vendor — same material, same skived spec. Choosing the small roll cost us roughly $1,900 over two years. A cost tracker catches that. Memory doesn’t.

Tooling consumables. If your finishing line runs 3M PPS cups, check the 3M PPS adapter chart against every gun model in the shop before you approve a purchase. We bought a replacement spray gun in 2024 without checking, and the adapter already on our shelf didn’t fit. That was a $260 pile of unusable cups and half a stalled batch. It’s a 30-second check on a published chart, and it only bites once — but it bites hard.

Branded consumables. And yes, if you’re buying branded adhesive or abrasives, look at the 3M logo and the lot code carefully. If you ask me, marketplace listings for tape are a red flag zone, and we’ve had one batch that behaved nothing like the real thing. Saving $40 on tape isn’t worth a failed bond on a $4,000 assembly.

Freight and masking. Here’s my penny-wise, pound-foolish moment: I saved $140 by switching a 12-sheet order to a slower LTL carrier. Two sheets arrived scuffed because the paper masking wasn’t rated for the extra handling, and we paid $600 for an expedited replacement plus a rescheduled install. Net loss around $460, plus a genuinely unpleasant phone call.

One more, because it comes up in every sustainability conversation now: if a sheet is marketed as “recyclable,” the FTC Green Guides (16 CFR Part 260) expect that claim to reflect actual access to recycling — not just a technical possibility. Ask which stream it goes into. In my experience the answer is usually more complicated than the marketing line.

The most frustrating part of sheet buying: the exact same conversation happens every time a PM finds a cheaper quote. You’d think a written spec would end the discussion, but interpretation varies wildly — especially around masking type, thickness tolerance, and whether “UV-resistant” means coated or inherent.

So which one do you buy?

Roughly, this is how I’d call it:

• Outdoor signage, display, glazing, anything judged on clarity: acrylic. Accept the breakage risk and design the mounting so there are no point loads.
• Machine guards, safety shields, forklift-adjacent anything: polycarbonate. No debate.
• Parts running above roughly 90°C in service: polycarbonate.
• Thermoformed parts with tight radii or deep draws: polycarbonate forms more forgivingly, though acrylic will do it if the geometry is gentle.
• Solvent-bonded assemblies: acrylic, unless you’re willing to move to mechanical fastening.

And one piece of process advice worth more than the material choice: ask “what’s not included” before you ask “what’s the price.” Every quote from every vendor we’ve worked with has gaps. The ones who fill those gaps in writing — masking type, thickness tolerance, freight terms, minimum order — tend to cost less in the end, even when their sheet price is higher.

I’ve learned that the hard way, twice. I don’t plan on a third.