What we typed
Dell Latitude replacement laptop battery, lithium-ion, 11.1V 4400mAh, no laptop
Laptops, batteries alone
Can you ship a laptop battery by itself?
Pull a laptop's battery out of the machine and it stops being the same shipment. USPS caps a standalone lithium-ion battery at 100 Wh, and an ordinary laptop pack sits comfortably under that line — a very different result from the much bigger cell inside an e-bike. We read the rule from USPS's own tariff and ran a real replacement laptop battery through our own checkout on 2026-08-21.
USPS wording, dated todayOur own checkout testedNo number invented
Under the line, not over it
A laptop pack usually clears USPS's 100 Wh ceiling with room to spare. That is the opposite finding from an e-bike battery.
The number that decides it: watt-hours
A laptop battery's rating is printed on the pack itself, usually as volts and either amp-hours or watt-hours directly. We used a common Dell Latitude replacement pack, 11.1V at 4400mAh, which multiplies out to about 49 Wh — not far off the 40 to 60 Wh most 13 to 16 inch laptop batteries carry.
| Battery | Watt-hours | Against the 100 Wh line |
|---|---|---|
| Dell Latitude replacement pack, 11.1V 4400mAh | ~49 Wh | Under, by about half |
| Typical 13–16 in laptop pack, 3 to 6 cell | 40–60 Wh | Usually under |
| MacBook Pro 16-inch pack (largest common laptop battery) | ~99–100 Wh | Right at the line |
That is the opposite result from an e-bike battery, which our own e-bike battery guide found running 360 to 910-plus Wh — several times over this same 100 Wh ceiling. An ordinary laptop pack is built to a size a person carries daily, and that keeps its watt-hour rating well inside the line most spare batteries run into trouble on.
What USPS Publication 52 actually requires
Section 349.244 of USPS Publication 52 covers a lithium-ion battery mailed without the equipment it powers — UN3480. Read from pe.usps.com on 2026-08-21: the general lithium-ion limits at 349.241 cap each cell at a 20 Wh rating and the battery itself at 100 Wh, and 349.244(b) caps the mailpiece at 5 lb. Section 349.244(d) sends it by surface transportation only, with an exception (349.244(e)) only when both the mailing point and the delivery point are inside Alaska. Section 349.244(c) requires the DOT lithium-battery mark naming UN3480 on the address side, next to the text “Surface Mail Only, Secondary Lithium Batteries – Forbidden for Transportation Aboard Passenger Aircraft” (or the equivalent wording for lithium-ion batteries).
Surface-only is not a penalty for being close to the 100 Wh line — it applies at any watt-hour rating up to that ceiling. A 20 Wh battery and a 99 Wh battery both mail by ground under this rule; only a battery that clears 100 Wh, or a mailpiece over 5 lb, falls outside it entirely.
What our own checkout returned
We described “Dell Latitude replacement laptop battery, lithium-ion, 11.1V 4400mAh, no laptop” to the SMKlog calculator on 2026-08-21, Berkeley Heights, NJ 07922 to Phoenix, AZ 85001. What came back follows unedited.
Packed box
9 × 6 × 2 in
23 × 15 × 5 cm
1.5 lb packed (0.68 kg).
Route
Berkeley Heights, NJ 07922
to Phoenix, AZ 85001
Both ZIPs live at quote time.
| Carrier | Service | Price | Estimated transit |
|---|---|---|---|
| UPS | Ground | $12.52 | 5-6 business days |
| USPS | Ground Advantage | $12.53 | 4-5 business days |
| FedEx | Ground | $22.59 | 6-7 business days |
Three carriers, three quotes, and not one of them was an air or expedited option — every service returned was an ordinary ground tier. That matches the surface-only rule above exactly: a battery well under 100 Wh still rides ground only, the same as a battery sitting right at the line. UPS and USPS landed within a penny of each other; FedEx Ground ran the most expensive of the three on this lane.
Packing a spare battery correctly
Cover the terminals
Tape over the contacts or leave the battery in its original plastic clamshell if it has one. A loose battery rattling against metal in transit is the scenario every rule on this page exists to prevent.
The mark goes on the outside
Check that the UN3480 label you use carries both pieces USPS asks for: the DOT battery mark and the surface-only text beside it. A laser print or preprinted sheet holds up to handling better than an inkjet page that can smear if it gets wet.
One battery, one small box
The 5-lb mailpiece cap applies to the whole package, not just the battery. A snug box built for one pack, not a bigger box with padding to spare, is both cheaper and the one most likely to stay under that limit.
Where these rules come from
- United States Postal Service, Publication 52, section 349, Class 9 Hazardous Materials — the 20 Wh cell and 100 Wh battery limits at 349.241; the 5 lb mailpiece cap, surface-only requirement and UN3480 marking text at 349.244. Read 2026-08-21.
- Price and result: our own capture against SMKlog production checkout on 2026-08-21, from Berkeley Heights, NJ 07922. Nothing on this page is a list price or an estimate.
Watt-hour ratings vary by laptop model and battery age; check the number printed on the actual pack rather than assuming it matches the example above. USPS revises Publication 52 without notice.
Common questions
Can I ship a laptop battery by itself?
Usually, yes, as long as it clears USPS's 100 Wh ceiling for a standalone lithium-ion battery. Our own Dell Latitude replacement pack, about 49 Wh, quoted $12.52 to $22.59 on ground service, captured against production 2026-08-21.
How many watt-hours does a laptop battery have?
Volts times amp-hours, using the numbers printed right on the pack. Our test battery, rated 11.1V at 4400mAh, comes out to about 49 Wh — roughly half of USPS's 100 Wh line for a battery mailed without the device it powers.
Why did every quote come back as a ground service?
USPS Publication 52, section 349.244(d), sends a standalone lithium-ion battery by surface transportation only, with an exception only for mail moving entirely within Alaska. Read from pe.usps.com 2026-08-21. That rule holds regardless of how far under 100 Wh the battery sits, which is why no air option showed up on any carrier in our own capture.
What has to go on the box?
The DOT lithium-battery mark naming UN3480, plus the exact wording USPS Publication 52 section 349.244(c) requires beside it: "Surface Mail Only, Secondary Lithium Batteries – Forbidden for Transportation Aboard Passenger Aircraft." Read 2026-08-21. The mailpiece itself is also capped at 5 lb under the same section.
Is this different from shipping a laptop with the battery installed?
Yes. An installed battery ships under UN3481, inside the laptop's own box, and rides ground service without the 5-lb mailpiece cap this page covers. A spare or replacement pack ships alone under UN3480, with its own 100 Wh, 5-lb, surface-only limits — the rules on this page.