TSA Power Bank Rules Explained
Power banks must always go in carry-on — never in checked bags. The size limits are based on watt-hours (Wh), not mAh.
| Capacity | TSA status |
|---|---|
| Under 100 Wh (under ~27,000 mAh) | ✓ Carry-on: unlimited. Checked: banned. |
| 100–160 Wh (~27,000–43,000 mAh) | Carry-on: max 2, airline approval. Checked: banned. |
| Over 160 Wh (over ~43,000 mAh) | ✗ Prohibited entirely |
To convert mAh to Wh: multiply mAh × 3.7 ÷ 1000. A 20,000 mAh power bank = 74 Wh — always allowed.
Related: Power Bank Checker Tool · International airline limits · Can I bring a power bank?