PLA filament, ranked by £/kg

What PLA filament is good at

PLA is the default filament for good reasons. It prints at low temperatures on an open printer, barely warps, holds fine detail, bridges well, and is the cheapest and most widely stocked material on the market. Nothing else is needed to run it: a standard brass 0.4 mm nozzle, a bed at 60 °C, no enclosure and no drying routine. If you are learning a printer, learn it on plain PLA — almost every failure you hit will be the machine rather than the plastic.

It is also stiffer than most people expect. For brackets, jigs, organisers, enclosure panels, prototypes, display models and anything that lives indoors and never gets hot, PLA is not a compromise choice. That stiffness is why a printed part often feels more solid in PLA than in a tougher, more flexible material.

Where plain PLA fails

Two weaknesses, both worth taking seriously. PLA softens from around 55 °C, so a part left on a car dashboard or a sunny windowsill through a summer will sag — the single most common disappointment with the material, and no print setting fixes it. And it is brittle: it snaps rather than bending, which makes it a poor choice for clips, hinges, snap fits and anything that takes a knock.

It is also a poor outdoor material. Sunlight and damp turn PLA chalky and weak over a season, and it offers little chemical resistance.

What to buy instead when PLA is the wrong fit

• It has to survive heat. PETG to roughly 75 °C with no enclosure needed; ASA or ABS to roughly 100 °C, both of which do need one.
• It has to bend rather than snap. PETG for a part that should give a little, TPU for one that genuinely has to flex.
• It lives outside. ASA, which is UV-stable.
• It just needs to be a bit tougher, printed the same easy way. The toughened blends sold as PLA+ or PLA Pro, which print almost identically to standard PLA.

If the choice is between the first two, PLA versus PETG works through it in detail.

Settings to start from

Nozzle 195–215 °C, bed 55–60 °C, cooling fan at full. PLA likes cooling — it is one of the few filaments where more airflow reliably improves overhangs and detail.

If your printer is enclosed, run PLA with the door open. Trapped heat softens the filament in the cold end and causes jams, which is the opposite of what an enclosure does for every other material here — see enclosed versus open-frame.

Buying: what actually differs

Between mainstream brands at similar prices, the meaningful differences are diameter tolerance and winding quality. A tightly wound spool with ±0.02 mm tolerance gives fewer failed prints than a loosely wound ±0.05 mm one, and that is worth a small premium. Colour and packaging are not.

Silk, matte and glow variants cost more because of the additive. Glow-in-the-dark in particular is abrasive and will wear a brass nozzle — see hardened versus brass nozzles.

PLA absorbs moisture more slowly than most filaments, so casual storage is survivable. It is not immune, though: a spool left open for months in a damp room will start popping and stringing. See filament storage.

How to read this table

The per-kilo column is the only number that compares listings honestly. A spool sold at 40% off can still be poor value, and a multi-spool bundle looks expensive until you divide by its total weight. We count bundles at their full weight, so a 4 × 1 kg pack and a single 1 kg spool sit on the same scale.

Where a listing does not state a usable weight we leave the per-kilo figure blank rather than guessing — a wrong ranking is worse than a missing one.