Written by: Timur Lesov

October 08, 2025

Updated on August 18, 2025

Key Takeaway: To ship efficiently with USPS-whether you need to know where to place labels, obtain free boxes, wrap parcels properly, understand prohibitions on mailing oneself, or decide between Ground Advantage and Priority Mail packaging-familiarity with USPS guidelines and available supplies is essential. This guide covers each topic in depth, ensuring packages are prepared correctly for timely, cost-effective delivery.

1. Label Placement on USPS Packages

Proper label placement ensures automated scanning, accurate routing, and on-time delivery. USPS’s Domestic Mail Manual and Postal Explorer specify clear standards:

• Address Side Orientation: All new shipping labels must appear on the same side of the package as postage and parallel to the longest side of the package.
• Clearance Requirements: Leave at least ½ inch from left and right edges, and 2¾ inches from the bottom edge of the face of a mailpiece to accommodate Optical Character Reader (OCR) machinery.
• Flat, Wrinkle-Free Application: Labels must lay flat with no gaps or wrinkles. Wrapping labels over seams or edges can obscure barcodes, causing delays or manual intervention.
• Avoid Corners and Seams: Place labels on a single planar surface away from corners and flaps to prevent barcode distortion or tearing during handling.
• Service Indicators:
• For Priority Mail, include the “P” service icon in the upper left corner of the label within a 1-inch square, and the “USPS PRIORITY MAIL” banner directly beneath the postage area in 20-point bold sans serif type.
• For Ground Advantage, affix the product name (“USPS Ground Advantage”) in the postage area or directly beneath it, ensuring at least 8-point type and a sans serif font.

2. Obtaining Free USPS Shipping Boxes and Envelopes

USPS provides free packaging for Priority Mail and Priority Mail Express, simplifying flat-rate shipments:

• Who Qualifies: Any sender using Priority Mail or Priority Mail Express may request free USPS-branded boxes and envelopes. Packaging must be used exclusively with the corresponding service.
• How to Order:
• Visit the USPS online store’s Free Shipping Supplies section, filter for “Free Shipping Supplies” and “Priority Mail” to view available envelopes and box sizes (e.g., small, medium, large flat-rate boxes).
• Choose single-piece or multi-pack quantities, all priced at $0.00 for Priority Mail packaging.
• Delivery typically occurs within 3–10 business days, though delays to 2–3 weeks have been reported in some areas.
• Pickup and In-Store Availability: Many post offices stock flat-rate Priority packaging; customers can pick up supplies in person subject to local stock.
• Restrictions:
• Free boxes are strictly for Priority Mail/Express shipments. Using them for First-Class or Ground Advantage violates terms and may incur additional charges or refusal of service.
• Once obtained, labels must remain intact; covering brand markings with tape or markers to repurpose packaging for other services is non-compliant.

3. How to Wrap and Pack a Box for Shipping

A well-packed box protects contents, minimizes movement, and prevents damage:

• Selecting Packaging:
• Use sturdy corrugated fiberboard boxes-single-wall for items under 10 lbs; double- or triple-wall for heavy (over 10 kg) or fragile items.
• Ensure the box size allows 2–3 inches of space on all sides for cushioning.
• Internal Cushioning:
• Wrap each item individually in bubble wrap, foam, or corrugated inserts. For fragile goods, use multiple protective layers and seal lids tightly.
• Fill all voids with packing peanuts, crumpled paper, or foam to prevent shifting. Shake the sealed box; add more cushioning if contents move.
• Sealing and Reinforcement:
• Use 2-inch-wide reinforced packing tape along all seams and edges; apply the “H-seal” method (taping across flaps and perpendicular to seams).
• Avoid staples, twine, or household masking tape. Tape over the label with clear tape only if necessary to prevent smearing, ensuring barcodes remain scannable.
• Labeling:
• After sealing, affix the shipping label on the largest side of the box, flat and wrinkle-free. Include a duplicate address label inside the package to aid delivery if the external label is damaged.

4. Mailing Yourself in a Box: Historical Curiosities and Legalities

While human stowaways in parcels capture public imagination, mailing a person through USPS is illegal and impossible under postal regulations:

• Historical Anecdote: In 1849, slave Henry “Box” Brown famously shipped himself from Virginia to Pennsylvania via Adams Express Company, not USPS, surviving 27 hours in a wooden crate.
• USPS Limits:
• Weight: Maximum package weight is 70 lbs.
• Dimension: No restriction prevents box size large enough to enclose an adult, but USPS disallows any live human as mail.
• Legal Prohibition: USPS’s Domestic Mail Manual forbids sending any living creature except for mailable aquatic organisms under specific conditions.
• Practical Considerations:
• Even if a person could fit, lacking life-support provisions (air, temperature control) renders the attempt fatal.
• Security screenings at mail facilities would detect unauthorized items far before shipment.

5. Can You Ship Ground Advantage in a Priority Mail Box?

Ground Advantage and Priority Mail have distinct packaging rules:

Conclusion: Adhering to USPS guidelines-proper label placement, using free Priority packaging correctly, wrapping parcels securely, understanding the absolute prohibition on mailing humans, and pairing services with correct supplies-ensures shipments are cost-effective, compliant, and delivered safely. Failure to follow these rules risks delays, additional charges, or package refusal. By leveraging free supplies and best-practice packaging methods, senders can optimize both Priority Mail and Ground Advantage services for reliable, efficient shipping.

• Strict Packaging Pairing: Priority Mail flat-rate supplies may be used only with Priority Mail postage. Submitting Ground Advantage labels on Priority boxes is expressly prohibited.
• Consequences of Misuse:
• USPS may refuse service, require repackaging, or charge Priority Mail rates based on packaging used rather than label applied.
• Resellers (e.g., Mercari) have reported forced repackaging at counters and potential overcharges if Priority packaging is used improperly.
• Recommended Practice: Always use your own box or a generic unbranded box for Ground Advantage shipments. Ground Advantage does not offer free packaging-customers must furnish suitable boxes and pay postage based on weight and distance.

Timur Lesov

Eco-freak, nerd, and green technology fanatic. I’m in favor of making eco-friendly living simple as well. I graduated from Berkeley in 2017. Studied environmental science and all things sustainability related. I create content and share simple tips for greening your everyday life. I think even small changes can make a huge difference and we can build a cleaner and more sustainable future.