Many travelers ask whether power banks are allowed on flights. The short answer is yes, but there are strict rules. Lithium power banks can only be placed in carry-on luggage. They are forbidden in checked baggage, because pressure and temperature changes in cargo hold raise safety risks. Most airlines accept power banks below 100Wh without special approval. 100–160Wh units need airline permission, while anything above 160Wh is banned. You can convert mAh to Wh with this formula: Wh = mAh × 3.7V ÷ 1000. The capacity label must be clearly printed on the shell. Blurry, removed or fake labels may lead to confiscation. Damaged, swollen or modified power banks are not permitted. Plan ahead for overseas trips and choose standard, well-marked portable chargers to avoid trouble at airport security.