Few things are as frustrating as opening a deck box to find your best foils curled like crisps. Foil curl is a common problem in Magic: The Gathering, and it's caused by moisture rather than age or poor quality. Once you understand why it happens, it's easy to prevent.
The short answer: foil cards curl because the foil front and paper back absorb moisture at different rates. Keep humidity stable, sleeve your cards, store decks in closed boxes, and flatten curled cards slowly under weight rather than with heat.
Why do foil MTG cards curl?
A card is made of paper layers with ink on top, and foils add a shiny foil layer to the front. The paper back absorbs and releases moisture from the air, but the foil front barely does, so the two sides expand and shrink by different amounts and the card bends. Players often call it "pringling".
Do non-foil cards curl too?
They can, but much less. Both sides of a standard card are paper, so they move together. Non-foil cards usually only curl after exposure to damp, spills or direct heat.
Is a curled card permanently damaged?
Mild curl usually isn't permanent and can be reduced. Severe or repeated curling can crease cards or separate the layers, though, and curled cards may be graded in worse condition when sold. It's far better to prevent than to fix.
How do I flatten a curled card?
Sleeve the card, place it between two flat, heavy books, and leave it in a dry room for several days. Check it and repeat if needed. Never use heat such as an iron or hairdryer, which can damage the foil and warp the card further.
How do I stop cards curling in the first place?
Store cards somewhere with stable temperature and humidity, away from bathrooms, kitchens, lofts, garages and outside walls. Keep them out of direct sunlight and away from radiators. Sleeved cards in a closed box are far better protected than loose cards on a shelf.
Do sleeves stop cards curling?
Sleeves slow down moisture exchange, which helps a lot. Double sleeving, with a perfect-fit inner sleeve inside a standard outer sleeve, gives the most protection for valuable foils. Our guide to single versus double sleeving explains what fits in which box.
Does silica gel help?
In long-term storage, yes. Silica gel sachets in a closed storage box absorb excess moisture and smooth out humidity swings. Dry out or replace them periodically, and don't overdo it, because very dry conditions can make cards bow the other way.
What's the best way to store a deck to prevent curling?
Keep the deck upright and snug in a closed, hard box: not loose enough to slide around, and not packed so tight the cards bow. SquadPod Slim holds a single-sleeved 100-card deck upright in two stacks, with a latch that keeps the lid shut, so cards stay flat and protected. For longer-term storage, see our guide to storing multiple Commander decks.
Can leaving cards in a car or garage cause curling?
Yes. Cars and garages go through big swings in temperature and humidity, which is exactly what makes foils curl. Bring your decks indoors after every game night rather than leaving them in a bag in the boot.
Does a hard deck box protect better than a soft one?
A hard box protects against crushing and bending, while soft boxes and pouches mainly stop scuffs. Neither seals out humidity completely, so where you store your cards still matters. Our comparison of fabric and hard deck boxes covers the trade-offs.
Why do new foils sometimes arrive curled?
Cards pick up moisture during manufacture, shipping and storage, and a foil opened in a different climate can start curling within days. Sleeve new foils promptly and keep them flat while they settle to your home's conditions. Mild curl from fresh packs often eases as they adjust.
Does card curl affect gameplay?
It can. A noticeably curled card is easier to pick out in your library, even face down, which can raise questions at the table. Sleeves hide most of that difference, which is another reason to sleeve any deck that contains foils.
What humidity is best for storing cards?
Stable humidity matters more than an exact number. Around 40–50% is a common recommendation for paper collectibles, and a cheap digital hygrometer will tell you what your room actually sits at. Big swings do more harm than a slightly high or low reading.
Are binders better than deck boxes for keeping cards flat?
For a collection, a binder with side-loading, PVC-free pages keeps cards flat and organised. For a deck you actually play, a hard deck box is more practical. Many players use both: binders for the collection and boxes for built decks.
How do I protect my commander from curling?
Commanders are often foil and get handled every game, so they're the cards most at risk. Double sleeve yours and keep it in a toploader when it isn't in play. Our guide to protecting your commander card covers the options.
SquadPod Slim Commander deck box
Holds 100 single-sleeved cards and 10 tokens in two side-by-side stacks, with your commander displayed in an included toploader behind the front window. Hinged lid, click-shut latch, five colourways.
More Commander guides
- How to Protect and Display Your MTG Commander Card
- How to Shuffle a Commander Deck Without Damaging Your Cards
- How to Store Multiple MTG Commander Decks Without Running Out of Space
- Fabric vs Hard Deck Boxes: Which Is Best for Your MTG Commander Deck?
Magic: The Gathering is a trade mark of Wizards of the Coast LLC. This is an unofficial guide and is not affiliated with, endorsed or sponsored by Wizards of the Coast. SquadPod® is a registered trade mark of Blubbercove Ltd.