Wireless charging is convenient, but the wrong case can slow down power transfer and even damage your phone. Check out what to look for when buying.
Wireless charging for smartphones has become standard, but its effectiveness often depends on an accessory we use every day – a case. Although the beginnings of this technology appeared back in 2009 with the Palm Pre and the Qi standard was established with the Nokia Lumia 920, it was not until Apple’s MagSafe system that wireless charging really took the masses by storm. Despite the progress, wireless power transfer comes with technical challenges, where the wrong choice of protective case can do more harm than good.
Wireless charging technology is inherently less efficient than traditional wired charging. While some wired chargers can deliver 80 watts or more, wireless charging is currently limited to 25 watts. To achieve this speed, the charging coils need to be perfectly aligned using magnetic rings, as required by the Qi2 or MagSafe standards. As energy is transferred through the back of the phone and the charger, it loses power and generates excess heat. Cases that are too thick, metal parts that are not properly positioned, or magnets that are too close together can make this problem worse, as they hinder the transfer of energy and trap heat.
Accessories such as popular grips (e.g. PopSockets) add unnecessary thickness to the back. Excessive overheating when using unsuitable accessories can damage the device - in extreme cases, the heat can soften the glue that seals the back of the phone, which can completely destroy its water resistance. That's why experts recommend choosing the thinnest possible cases that are adapted for inductive charging. Good examples are the Spigen MagFit, which has only an extremely thin layer of polyurethane on the back, or the Speck Presidio 2, which uses a special internal cutout to reduce the barrier between the charger and the device.
For users of devices that don't have built-in magnets (like the Samsung Galaxy S26 Ultra), a proper case with a built-in magnetic ring is the only way to fully utilize the latest Qi2 chargers. Be warned, though – some cases with cheaper mechanisms can loosen the magnetic ring over time. Always check user reviews and independent compatibility tests before purchasing, as a manufacturer's promise of wireless charging support is often not enough in practice.
