Mailer Box Dimensions: Size Chart Guide for E-commerce

Mailer box dimensions every business should know: small, medium. Large mailer sizes with dim-weight math and unboxing tips for e-commerce brands. At Discount Box Printing, we make custom packaging boxes to any size, factory-direct across the United States. This guide covers sizes, tips. Cost points so you pick right the first time.

• Small: 6 × 4 × 2 in — jewelry, samples
• top: 8 × 6 × 2 in — books, tees
• Medium: 10 × 8 × 3 in — subscription
• Large: 12 × 9 × 4 in — full buy
• XL: 14 × 10 × 4 in — apparel bundle
• Style: roll-end tuck or wing-lock
• Wall: E-flute (1/16 in) or F-flute
• MOQ: 100 pcs, no setup fee

What Is a Mailer Box?

A mailer box is a self-locking corrugated carton with an integrated lid. It ships flat, folds in seconds, and closes without tape. The inside face prints full color. Turns every parcel into a small brand moment. Mailer boxes are the top pick for direct-to-consumer e-commerce.

Small Mailer Box Sizes (Under 8 Inches)

Small mailers cover single-item ships. A 6 × 4 × 2 fits jewelry, a phone case, a sample pack, or a soap bar. A 7 × 5 × 2 fits a coffee mug or a small tumbler. Both ship at USPS Ground first-class rates for lighter loads.

top Mailer Sizes (8 to 10 Inches)

The 8 × 6 × 2 is the mailer workhorse. It fits paperbacks, t-shirts, small kits, and slim gift sets. A 9 × 6 × 3 gives extra depth for a bundle. A 10 × 8 × 3 fits a full subscription box drop. See our full range on custom mailer boxes.

Large Mailer Sizes (12 Inches and Up)

A 12 × 9 × 4 mailer handles a full buy or a two-item bundle. A 14 × 10 × 4 wraps around folded apparel or a beauty box drop. A 16 × 12 × 6 covers a shoe pair or a small hardware kit. Past 16 in, most brands switch to a corrugated shipper.

Mailer Box Style Options

Roll-end tuck mailers open flat with a smooth inside face. The classic e-com look. Wing-lock mailers snap shut without tape for faster pack times. Two-piece mailers give a true lid-and-base experience for top goods. Pick the style around your pack line and brand mood.

Dim Weight and Mailer Cost

shippers bill on the higher of actual or dim weight. Dim = L × W × H / 139. An 8 × 6 × 2 has a dim of 1 lb. A 12 × 9 × 4 has a dim of 4 lb. Trim height first when you need to cut cost. A flat mailer bills lower than a tall one.

Common Mailer Sizing Mistakes

Using one size for every SKU line. Over-sizing by 2+ inches and paying dim weight for empty space. Skipping the sample and finding out the size is wrong on the 500th buy. Using single-wall for a heavy 5+ lb load when double-wall would hold up better.

Sizes & Dimensions Chart

top mailer box sizes matched to the SKUs each one fits best.

Wholesale Cost and Ordering

Custom sizes cost the same as stock sizes in bulk. So there is no reason to force an item into a poor fit. We make the boxes ourselves. Means no reseller markup and no setup fee. Low MOQs let you test a size before you scale. Send a rival quote through Beat My Quote and we will try to come in lower.

1. Request a free quote. Share the size, the style, the print, and the count.
2. Get a free proof. Our team preps a dieline and a 3D mockup at no cost.
3. Approve and we print. We build factory-direct after sign-off.
4. Free US delivery. Your boxes ship to your door in 10 to 12 days.

Explore More

• Ecommerce Packaging Dimensions — online store sizes.
• Shipping Box Size Chart — shipper caps.
• Corrugated Box Dimensions — heavy-duty grades.
• top Packaging Box Dimensions — by field.
• Shop Custom Mailer Boxes — low MOQ.