A first custom-printed mailer order has a predictable bottleneck, and it usually isn't the press. It's the file loop: artwork that arrives as a JPEG, colors described as “our blue”, a logo that runs across the flap fold. Each round trip adds days before a plate is made.
Flexographic printing transfers ink from plates made from your artwork — one plate per color, per side. That's why the file matters so much, and why getting it right the first time is worth a checklist.
1. Send vector artwork
Send vector files — AI, EPS, or a vector PDF — with fonts converted to outlines. A logo saved from a website is usually a low-resolution image that can't be scaled cleanly to print size, and it's the most common reason a first order stalls.
2. Specify colors by Pantone
Name every color by its Pantone reference. “Our blue” looks different on every screen; a Pantone number is a target the press can match. Count your colors per side as well: up to six per side is available, and every color is its own plate.
3. Keep artwork out of the seals and the flap
The side seals, the bottom seal and the adhesive flap aren't print areas you control. Ask for the printable area for your size, and keep text and the critical parts of your logo clear of the edges and the fold — so nothing ends up sealed over, trimmed, or folded out of sight.
4. Plan the barcode and any warning
If you print a barcode or QR code, give it clear space and keep it on a flat area away from seams, so it scans. If the bag needs a suffocation warning, its print size is set by the bag's dimensions — design the warning panel into the layout from the start instead of squeezing it in at the end.
5. Say which faces print
Front only, or front and back. Two-sided printing is common on brand mailers — a logo on the front, a message or return instructions on the back — and each face's colors are counted separately.
6. Approve the proof before plates
Plates are made from the approved proof, and they're one-time tooling: once made, they're reused on every repeat run of the same artwork. That's also why a change after approval isn't free. A new design means new plates.
The minimum, and why it exists
Custom-printed runs start at 50,000 pieces per artwork. Below that, plate and press setup dominate the per-piece price. If you're not there yet, start on unprinted stock mailers, which ship from a single case, and move to print when the volume justifies it — our guide to custom-printed mailer MOQs and lead times walks through that path.
Send the files, the sizes and the quantities, and we'll quote in 24 business hours.