What you can ship at a USPS self-service kiosk in one sentence
Most domestic Priority Mail and Priority Mail Express items up to 70 lb and up to 108 inches in length plus girth can be processed at a kiosk if they meet packaging rules and are eligible for automated handling; some items must be hand‑scanned by a associate. Square and flat large envelopes (FLAT) and small parcels under these thresholds typically qualify, while hazardous materials, lithium batteries, certain liquids, and regulated items require clerk assistance or are not permitted at kiosks.
USPS kiosk basics and when to use them
USPS self-service kiosks are designed for fast, label‑only transactions, including shipping, changing service types, adding delivery instructions, and returning or changing items. They work best for pre‑packaged, non‑hazardous items that fit automated sorters. If you are unsure whether an item is eligible, it is usually faster to start at a kiosk and let the system or an associate advise you before completing the sale.
Key measurements that determine kiosk eligibility
Two dimensions control whether a package can go through a kiosk: total weight and combined length plus girth. Understanding these thresholds helps you prepare the package before you arrive and avoid delays.
Weight limits by service
Weight limits vary by service, but for most parcel services the ceiling is 70 lb at the self‑service point. Flat envelopes have lower weight caps tied to the product selected. Always enter the exact weight on the kiosk scale; if the system cannot sell a product at the measured weight, it will block the transaction or require associate verification.
Dimensional limits: length and girth
For most USPS services the combined length and girth maximum is 108 inches. Length is measured on the longest side, and girth is the perimeter of the widest section perpendicular to the length. Packages exceeding this combined measurement cannot be transported on fully automated systems and must be handled by clerks, so they cannot be completed at a kiosk.
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Maximum weight (parcel services) | 70 lb (31.8 kg) | USPS official service guides |
| Maximum combined length + girth | 108 inches (274 cm) | USPS official service guides |
| Typical length limit for large parcels | Length alone must generally be under 70 in when used with high‑girth items | Derived from combined limit guidance |
| Flat Large Envelope (FLAT) weight limit | Up to 13 oz (approx. 0.8 lb) for basic FLAT; higher weights treated as parcels | USPS official classification rules |
| Prohibited at kiosks | Hazardous materials, certain lithium batteries, liquids requiring special handling | USPS dangerous goods regulations |
Package requirements that affect kiosk acceptance
Beyond weight and dimensions, how you package the item matters. The package must be able to travel through automated sorters without getting stuck or causing jams. This means avoiding soft packaging that collapses, non‑machinable shapes, or items that could damage scanners. If the system cannot scan the barcode or the item is flagged by sensors, the kiosk will stop the transaction and direct you to a clerk.
Mailing requirements that kiosks enforce
- Readable, machine‑scanned barcode on the same side as the address
- Rigid, uniform shape that passes through conveyor rollers
- No overhanging contents, protruding sharp edges, or irregular lumps
- No prohibited or limited quantities of hazardous materials
- Acceptable postage purchased through the kiosk or linked account
Examples of items that typically qualify and those that do not
Items that usually pass kiosk validation include padded envelopes within weight limits, small electronics in rigid boxes, books in soft packaging (if within dimensional limits), and media that are not regulated. Items that usually require clerk assistance include furniture, oversized pallets, items with lithium batteries installed, hazardous materials, and liquids in quantities restricted by dangerous goods rules.
When a package must be processed by a clerk
You must see a USPS associate if your item is over the weight or dimensional limits, is classified as hazardous or regulated, contains lithium batteries that require special handling, has irregular dimensions or shape that could jam equipment, or needs special services such as signature‑required delivery not supported by the kiosk flow. Associates can also help you weigh, measure, and choose the best service if you are near a threshold.
How to verify eligibility before visiting a kiosk
Check the current Product and Service Guide (PSG) for precise limits and restrictions, measure your package length and girth and weigh it on a standard scale, and label it with a readable barcode and valid address. If you are close to a limit, consider alternative packaging or plan for clerk assistance at the counter.
Frequent questions about kiosk package size
If you are still unsure, here are concise answers to common questions about what you can ship at a self-service kiosk.
Can I ship a box that is 40 inches long at the kiosk?
Yes, provided the length plus girth stays at or under 108 inches and the weight is within limits for the selected service. If the combined measurement exceeds 108 inches, you will need a clerk.
What happens if my package is under 70 lb but over 108 inches in length plus girth?
The kiosk transaction will not be completed. You will be directed to see an associate for manual processing or to choose an alternative service that does not use automated sorters.
Are padded flat rate envelopes limited by the 108‑inch rule?
Flat Rate envelopes are subject to size and weight classifications. If a Flat Rate package exceeds weight limits for that class or violates dimensional classifications for automated processing, it must be handled by a clerk.
Can I ship a small lithium battery at a kiosk?
Lithium batteries often require special handling, documentation, or packaging exceptions. In many cases you must see an associate; kiosks typically block these transactions unless the battery is installed in a device and the system is configured to handle it.
Can I ship items longer than 18 inches on either side of the address on the same side?
Length is measured on the longest dimension of the package. As long as length plus girth is within 108 inches and the item is otherwise eligible, size on one side of the label does not prevent kiosk processing.