A guide to what belongs in your carry-on (and never in checked), how the 0–100 / 101–160 / >160 Wh tiers work, and what’s allowed when you mail batteries inside the U.S. Now with a brand-new section that summarizes the most common airline-by-airline rules for U.S. carriers.
Carry-on only
Carry-on preferred
Three tiers that matter
Wh tiers explained
These tiers apply to spare lithium-ion batteries and power banks. Installed batteries inside a laptop follow device rules (carry-on preferred; checked only when fully powered off).
| Tier | Typical items | Carry-on | Checked | Practical notes |
|---|---|---|---|---|
| 0–100 Wh | Most phone/power banks ≤100 Wh; many laptop spares | Allowed (terminals protected) | Not allowed (spares) | No hard “count” limit for personal use in the U.S.; airlines may set their own limits. |
| 101–160 Wh | Large laptop packs; pro-grade power banks | Usually allowed with airline approval (commonly ≤2 spares) | Not allowed | Ask your airline before you fly; rules can vary in practice. |
| >160 Wh | Very large packs | Not allowed | Not allowed | For cargo shipments, specialized hazmat rules apply; not for passengers. |
Air travel: carry-on vs checked
Carry-on
- Power banks & spare batteries: carry-on only.
- Keep terminals covered; pack each battery to prevent contact with metal.
- Place any charging device so crew can see it while in use.
Checked baggage
- Spare lithium batteries and power banks: not permitted.
- Device with installed battery: permissible when fully powered off and protected from accidental activation. Carry-on remains best practice.
Wh calculator + real-world examples
Formula: Wh = (mAh × V) / 1000
Result: — Wh
- 20,000 mAh @ 3.7 V → ~74 Wh → in 0–100 Wh (carry-on allowed).
- 30,000 mAh @ 3.7 V → ~111 Wh → in 101–160 Wh (get airline approval; commonly ≤2 spares).
- 50,000 mAh @ 3.7 V → ~185 Wh → >160 Wh (not allowed on passenger flights).
Airline-by-airline rules (U.S. carriers, 2025)
Summary for typical consumer batteries and power banks. Mobility devices (wheelchairs, medical) have separate allowances.
American Airlines
- Spare batteries: carry-on only.
- ≤100 Wh: up to 4 spares.
- 101–160 Wh: up to 2 spares (approval typically required).
- Installed batteries in devices: carry-on preferred; if checked, device fully off.
Delta Air Lines
- Spare batteries: carry-on only.
- 101–160 Wh: up to 2 spares with approval.
- Overall spare cap: up to 20 spares (≤100 Wh) per person for personal use.
- If a carry-on is gate-checked, remove all spares.
United Airlines
- Spare batteries: carry-on only; separate and cover terminals.
- 101–160 Wh: up to 2 spares with airline approval.
- Gate-check reminder: remove spares and power banks before checking at the gate.
Southwest
- Spare batteries & power banks: carry-on only.
- In-use power banks must stay visible (not buried in overhead/underseat bags).
- Do not charge devices with a power bank stowed out of sight.
Alaska Airlines
- Spare batteries: carry-on only.
- Follows the common 0–100 / 101–160 Wh tiers.
- Check your itinerary if codesharing with non-U.S. carriers.
JetBlue
- Spare batteries: carry-on only.
- Up to two spares not exceeding 160 Wh each; label compliance expected.
- UN 38.3–tested types recommended.
Hawaiian
- Spare lithium batteries: carry-on only; protect terminals.
- Devices with installed batteries: carry-on whenever possible; fully off if checked.
Spirit
- Spare batteries: carry-on only.
- Typical rule: each installed or spare battery ≤ 100 Wh for consumer items.
- Smart luggage accepted only if the battery can be removed.
Heads-up: Some airlines mirror the general U.S. baseline, while a few add stricter limits (e.g., quantity caps or visibility rules for in-use power banks). Always check your booking app/email for last-minute updates.
Shipping inside the U.S. (consumer & small business basics)
USPS (Postal Service)
- Standalone lithium-ion batteries & power banks: generally ground-only (surface) in domestic mail.
- In or with equipment: more options exist when properly packed and marked.
- Always protect terminals and prevent movement inside the parcel.
DOT / PHMSA (hazmat rules)
- All carriers follow Hazardous Materials Regulations; lithium batteries have case-by-case packing/marking.
- Air cargo in commerce has extra limits (state of charge, package counts). Work with your carrier/compliance team.
- UN3480 = lithium-ion batteries (standalone).
- UN3481 = lithium-ion batteries contained in / packed with equipment (e.g., laptop).
- Lithium-metal equivalents: UN3090/UN3091.
Pack-right checklists
Carry-on (do this)
- Power banks & spares only in carry-on, terminals covered.
- Devices in checked bags: fully powered off and protected.
- Keep in-use power banks visible to cabin crew.
Never do this
- Put power banks in checked baggage.
- Travel with damaged/swollen batteries.
- Let loose batteries touch metal objects (coins, keys).
FAQ
Can I put a ≤100 Wh power bank in checked baggage?
No. Power banks are spare lithium batteries and belong in your carry-on only.
How many spare batteries can I bring?
U.S. baseline: no fixed count for ≤100 Wh beyond “personal use,” but airlines may set limits. For 101–160 Wh, expect airline approval and a common limit of up to two spares.
Is a laptop with the battery installed allowed in checked baggage?
Yes, but only when fully powered off and protected from accidental activation. Whenever possible, keep valuable electronics in your carry-on.
What about swollen or damaged batteries?
Do not travel or ship with them. Replace and dispose through proper e-waste channels.