The top 3 most heat-resistant filaments
The absolute top-tier material is PEEK (or its relative PEI/ULTEM): it maintains its shape well above 200°C, but you can only print it on high-end industrial printers. For a standard 3D printer, the practical top 3 looks like this:
- Polycarbonate (PC): remains stable up to about 110 to 140°C.
- Nylon (PA): strong and heat-resistant, especially when reinforced with carbon fiber.
- ASA and ABS: go up to around 100°C.
For comparison: PLA, the most popular filament, starts to soften at just 55°C. In a hot car, your print will be deformed in no time.
What does heat-resistant actually mean?
Before choosing a heat-resistant filament, it helps to understand two concepts. The first is the glass transition temperature (Tg): the temperature at which a plastic becomes soft and pliable. It’s not melting, but your print will lose its rigidity and shape. You can read more about this at glass transition temperature.
The second is the heat deflection temperature (HDT): the temperature at which a part begins to sag under load. For functional parts, the HDT is often the most accurate metric, because a print sitting on a table can withstand more heat than one that also has to bear weight.
In short: the higher the Tg and HDT, the more heat your filament can handle without deforming. Keep in mind that the stated values are measured in a laboratory. In practice, load, geometry, and print quality also play a role.
These are the most heat-resistant materials
Below you'll find the most commonly used filaments, ranked from most to least heat-resistant.
PEEK and PEI (ULTEM): up to 200°C
These are the true heat champions, with heat deflection temperatures exceeding 200°C. You'll find them used in the aerospace and medical industries.
Nothing comes close in terms of heat resistance: they are unmatched in strength, chemical resistance, and dimensional stability at extreme temperatures.
The challenge lies in processing them. You can only print these materials on industrial printers with an extruder capable of reaching 400°C and a heated chamber, and the filament itself is pricey. For most people, it’s not a realistic option.
Polycarbonate (PC): up to 145°C
Polycarbonate is the most heat-resistant filament you can still use on a high-end hobby printer, with a glass transition temperature around 145°C.
Beyond its heat resistance, the material is incredibly strong, rigid, and impact-resistant—a great combination for functional parts. On the flip side, PC warps easily during printing, which means you need a closed printer with a heated chamber. It also absorbs moisture from the air, so you'll need to keep it stored in a dry environment.
Nylon (PA)
Nylon combines heat resistance with toughness and wear resistance. When reinforced with carbon fiber it becomes even stiffer and more heat-resistant.
It’s strong, flexible where it needs to be, and handles heat and friction well, making it excellent for functional parts like gears and hinges. The downside is that nylon is extremely hygroscopic and must be bone-dry before it goes into the printer, or the print will fail. It also requires higher printing temperatures than most filaments.
ASA: up to 100°C
ASA withstands heat up to around 100°C and is also highly resistant to UV and weather. That makes it a favorite for outdoor use.
That combination of heat resistance and UV stability makes it tough: it won't discolor or weaken in the sun, which makes ASA the top choice for parts used outdoors. It can warp during printing and releases fumes, so an enclosed printer and good ventilation are recommended.
ABS: up to 100°C
ABS is very similar to ASA and also holds up to about 100°C. It is a bit cheaper, but less UV-resistant.
For a great price, you get excellent heat resistance, and the material is easy to post-process by sanding, gluing, or using acetone. It does have a tendency to warp, gives off a strong odor while printing, and discolors in the sun. You can read how it compares to an easier alternative in ABS versus PETG.
PETG: up to 80°C
PETG is in the middle of the pack when it comes to heat, with a glass transition temperature around 80°C. Enough for warm water, but not enough for real heat.
It prints easily and is strong, waterproof, and reasonably heat-resistant for everyday use, making it a nice all-rounder. However, it falls short for sustained heat or heavy mechanical stress at high temperatures.
Which heat-resistant filament should you choose for your print?
The best choice depends on where your print will end up. A few common situations:
- In the car (dashboard, phone mount): ASA or ABS, because it can easily reach 70 to 80°C behind the windshield.
- Outdoors in sun and rain: ASA, because of its combination of heat and UV resistance.
- Near an engine, heater, or electronics: polycarbonate or nylon, for the highest heat resistance.
- Functional parts that get hot and wear down (gears, guides): nylon, preferably with carbon fiber.
- Warm water or the occasional hot liquid: PETG usually does the trick.
- Indoor decoration without heat: PLA is fine and the easiest to use.
Still not sure? Our guide on how to choose the right filament will help you on your way.
The printer and the print affect heat resistance
Choosing a heat-resistant filament is half the battle. The other half depends on how you print it. Materials like PC, nylon, ASA, and ABS warp easily if they cool down too quickly. That’s why it’s best to print them in a closed printer with a heated chamber, which retains the heat.
If you need to handle even more heat, carbon fiber reinforcement helps: filaments like PA-CF and PC-CF are stiffer and hold their shape at higher temperatures. Wall thickness and infill also play a role, as a solid, thick part withstands heat better than a thin, hollow print. You can even make PLA slightly more heat-resistant with a heat treatment (annealing), though it can easily deform during the process.
In short: the material sets the upper limit, but the printer and the printing method determine whether you actually reach it.
Get your heat-resistant part printed professionally
Heat-resistant materials like PC, nylon, and ASA sound appealing, but they are trickier to print than PLA. Warping, moisture, and the right temperature make the difference between a part that lasts for years and one that deforms after a single hot day.
You don't have to worry about that. We print your part in the right heat-resistant material, using printers that can handle these filaments properly. Not sure which material is right for you? Use our material selector or request a quote. This way, you can be sure your print is resistant to the heat it's intended for. Want to know more about materials and 3D printing? Dive into our knowledge base.
