Custom mailer box design: what to print on each panel, inside and out

Surprise table. Good custom mailer box design starts with one question: which panel does the customer see first, and which one does the carrier cover with a label? Put your logo where the eye lands when the box sits on a porch, keep the top clear enough for a shipping label, and save the message for the inside lid, which is the one panel nobody else ever sees.

Below, panel by panel: what each print choice costs on a 9 x 6 x 3 inch mailer, the mistakes that show up on a proof, and a layout you can copy.

The six panels of a mailer box, and who sees each one

A roll-end tuck-front mailer (the box usually meant by "mailer") folds out of one sheet into six areas worth designing for:

The outside works for everyone who handles the box. The inside works only for the person who paid for what's in it. Design them as two different jobs, and the box gets easier.

Design the lid around the shipping label.

This is the step most first designs miss. The top of the lid is your biggest, best-lit panel, and it's also where the label goes.

USPS asks shippers to put all labels on the same side and not fold them or bend them over edges (opens in a new tab), and in practice that side is the lid. A standard 4 x 6 inch label takes up close to half of a 9 x 6 inch top. So if your logo sits dead center, somebody in your packing room will stick a label straight across it.

Two layouts that survive the label:

• Logo in one corner or along one edge, with a clear block of plain color or white about 4.5 x 6.5 inches for the label.
• Logo on the sides, pattern on top. A repeating pattern still looks good with a rectangle stuck over part of it. A single centered logo doesn't.

Want a clean top? Ship the mailer inside a plain outer carton, and the label goes there instead.

The front flap and the sides

The front tuck flap is the first thing a customer's thumb touches. It's small, it bends, and part of it disappears inside the box when it's closed. Keep it simple: a short word ("hello", "open me", your name), a small icon, or plain color. Long text on a flap gets cut by the fold.

The long sides matter on a doorstep, where a box often lands on its side, and in a stack at a 3PL, where the sides face out. One logo per long side is plenty, plus your website in type no smaller than about 10 point.

What to print on the inside

Inside print is where custom mailer box design stops being about recognition and starts being about the moment the lid comes up. It's also the one choice that costs a real amount extra.

On a 9 x 6 x 3 inch mailer, full color outside only is about $2.21 each at 250 and $1.57 at 500. Printing outside and in is about $2.61 at 250 and $1.85 at 500. That's 40 cents a box at 250, or about $100 on the run.

Is it worth it? Here's our honest take:

• Worth it when the box is the gift, when people film or photograph unboxings in your category (beauty, candles, jewelry), or when the inside lid replaces a printed insert card you'd otherwise pay for.
• Not worth it when the product sits in its own retail carton inside the mailer, or when the box mostly travels to wholesale customers who'll open it with a box cutter in a stockroom.

If you do print inside, use it for one thing: a short thank you, a QR code to reorder, or care instructions. Nobody stands at the door reading a full page.

One color, full color, and the board underneath

What you print on matters as much as what you print. Here's what the same 9 x 6 x 3 inch mailer costs with the main print choices:

A one-color design on kraft is the cheapest way to get a branded mailer, and it hides scuffs better than any other option, because brown board looks fine when it's been rubbed. Full color opens up photos, gradients, and patterns, and it's what you need for a design that covers every panel. If you're choosing between a spot color and full color for a logo, our guide to CMYK vs Pantone walks through when a matched ink earns its cost.

Blackboard is the one to think twice about. A one-color design on black is about $2.14 at 250, a little cheaper than full color on white, and it looks sharp. But corrugated edges and folds show any rubbing, and a dark box shows it more.

Folds, edges, and the dieline

Your artwork gets printed flat and then folded, and the folds are where designs go wrong. Every mailer starts from a dieline, the flat map of cut lines and fold lines, and your design has to be laid onto it, not just onto a picture of a box.

Four rules that catch most problems before a proof:

1. Keep text and logos at least a quarter inch from any fold. On a corrugated mailer, the fold rounds over, and anything sitting on it bends out of sight.
2. Run background color past the cut line. That's the bleed. Without it, a slightly off cut leaves a thin white edge.
3. Check which way each panel faces. On the flat sheet, some panels are upside down relative to others. A logo that looks right on the flat layout can end up upside down on the front flap once folded.
4. Avoid a solid dark color right across a fold. Heavy ink coverage can crack along a crease and show the board underneath as a pale line.

You can make an accurate flat layout for your own size with our free dieline generator, then print it on paper at full size, cut it out, and fold it. Ten minutes with scissors shows you exactly where the flap hides your text.

Design for the trip, not just the photo

A mailer box gets thrown in a truck, stacked, dropped on a porch, and rained on before anybody opens it. Design for that.

• Fine detail on the outside wears off at the corners. Keep thin lines and small type away from edges, which take the most rubbing.
• A matte or gloss laminate protects the print, at about 21 cents a box at 250 on top of outside and in printing. Our guide to packaging finishes covers which one suits a box that's handled a lot.
• Think about returns. In apparel especially, a box often makes a second trip. Our post on packaging for clothing brands explains why a design with nothing seasonal on the outside lasts longer.
• Seasonal art belongs on something cheaper than the box. If you want a holiday look this November, keep the mailer the same all year and add a printed sleeve, sticker, or tissue for the season. Our guide to custom packaging sleeves shows how that works.

A worked example: a candle brand's first mailer

Say you sell candles online and your jar fits a 7 x 5 x 4 inch mailer with an insert. You want the box to look like yours without paying for every panel.

Here's a layout that works. On the lid, your logo in the top left corner at about 2 inches wide, with the rest of the lid in your brand color and a clear area on the right for the label. On each long side, the logo again, centered. On the front flap, just your brand color. On the inside lid, a short line ("Light it, then read this: trim the wick to a quarter inch before every burn") and a QR code to reorder.

That's full color outside and in, because a candle box gets opened slowly and the inside lid gets seen. Selling to boutiques by the case? Drop the inside print and save the money. Our page on mailer boxes for candles has the insert options for holding a jar upright.

How to brief your box design

You don't need to be a designer to get good custom mailer box design. Tell whoever lays it out four things:

1. The inside dimensions of the box, in inches. If you're not sure yet, our guide to custom mailer box sizes helps you pick one.
2. Your logo as a vector file (AI, EPS, SVG, or a PDF saved from those), plus your brand colors.
3. Which panels you want printed, using the panel names above, and whether the inside is printed.
4. How the box ships: with a label on the lid, inside an outer carton, or to stores by the case.

Our design help is free, and the logo b guide explains what's included. You'll get a flat proof of every panel before anything prints, which is the moment to check the flap and the label area once more.

Custom mailer box design mistakes to avoid

• A big logo dead center on the lid, which disappears under the shipping label.
• Text on the front flap that wraps over the fold or hides inside the box.
• Designing on a 3D mockup only. Mockups are great for a feel, but the printer works from the flat layout. Check that too.
• Printing every panel because you can. Each panel you fill is another place a fold, scuff, or label can go wrong.
• Forgetting what goes inside. If the product sits in an insert, the insert covers most of the inside base. Don't put your best art where the tray will hide it.

Try it before you order

Our 3D box designer puts your logo on a mailer at your size, and nothing leaves your browser unless you save it. For a box in your hands, a sample pack costs $9.95 in shipping, credited on your first order. The custom mailer boxes page prices any size from 100.

Key takeaways

• Custom mailer box design is panel by panel: the outside is for everyone who handles the box, the inside is only for your customer.
• Leave room on the lid for a 4 x 6 inch shipping label, or put your logo in a corner and on the sides.
• On a 9 x 6 x 3 inch mailer, full color outside is about $2.21 at 250; adding inside print brings it to about $2.61.
• Keep text a quarter inch from folds, run color past the cut line, and check which way each panel faces on the dieline.
• A one color logo on kraft is the cheapest branded mailer, from about $1.71 at 250.

Common questions