Yes, you can absolutely take a battery-operated or rechargeable electric toothbrush in your hand luggage (carry-on) in 2026. In fact, most security agencies, including the TSA and UK Department for Transport, prefer that you keep devices with lithium-ion batteries in your carry-on rather than in checked luggage. This is because lithium batteries pose a very small risk of "thermal runaway" (catching fire); if this happens in the cabin, the crew can quickly extinguish it, whereas a fire in the cargo hold is much more dangerous. You do not need to remove the toothbrush from your bag at the security checkpoint, as it is considered a small personal electronic device. If your toothbrush uses standard alkaline (AA/AAA) batteries, those are also perfectly fine in both carry-on and checked bags. One "pro tip" for 2026 travelers: ensure your toothbrush has a "travel lock" or is packed in a hard case to prevent it from accidentally vibrating inside your bag, which can lead to an awkward bag search or a dead battery upon arrival at your hotel.