Custom Padded Paper Mailers

Sizing a Padded Mailer

Padded mailers are measured by their outside size, and the padding takes up some inside space, usually 5–10 mm on each dimension. Measure your item, add the thickness of the item to both the length and width, then add a little more for the padding. A paperback of 130 x 200 x 20 mm, for example, fits comfortably in a mailer of about 180 x 265 mm.

Watch the Large Letter limits if you want the cheapest postage: 353 x 250 x 25 mm and up to 750 g. A flat item of up to about 15 mm thick usually stays within that limit in a padded mailer. Thicker items move into the small parcel band.

If you post several items together, such as a notebook with a pen and a card, lay them flat in the order you will pack them and measure the stack. That gives a more accurate size than measuring each item separately. Our guide to measuring a product for packaging covers stacked contents.

Print and Closure Options

The outer paper is usually kraft brown or white. Kraft gives a natural look and hides postal marks; white shows colours brightly. One or two-colour logo printing is the most popular choice, often a logo on the front with a short message or a social media handle on the back. Full-colour print is possible on white mailers for brands that want a bold pattern.

A peel-and-seal adhesive strip closes the mailer quickly and securely. A second strip makes the mailer returnable, and a tear strip lets customers open it neatly without scissors. Keep a clear area on the front for the address label, roughly 100 x 150 mm, so your artwork is not covered.

If you send a lot of orders, ask for the mailers to be packed in bundles of a fixed count. It makes stock checks quicker and lets packing staff grab a known quantity for each shift. Print coverage on kraft and white paper is compared in the print and finish options guide.

Senders That Suit a Padded Envelope

Online bookshops and stationery brands are the biggest users, followed by jewellery and accessory sellers, cosmetics brands and gift shops. Subscription services posting small monthly items use printed paper mailers to keep postage low. Artists and illustrators use them for prints mounted on card. Fashion accessory brands use them for socks, ties and scarves where a box would be overkill.

Many brands also keep a few larger mailers in stock for bundle orders, which saves reaching for a box.

Charities and membership organisations use printed paper mailers to send welcome packs, badges and membership cards to new members, and small publishers post advance copies in branded mailers so the first impression arrives before the book is opened.

Craft sellers on online marketplaces like the natural look of kraft mailers, which matches handmade products such as candles in tins, knitted accessories and leather keyrings. Clothing sellers who need a waterproof bag use the poly mailer bags for clothing orders instead.

Packing Tips

Do not overstuff. A mailer that is bulging at the seams loses most of its padding effect, because the padding is already compressed before the knocks start. If a product only just fits, move up one size. For items with sharp corners, such as hardback books, a thin card wrap around the corners adds protection.

Seal the strip firmly from one end to the other, pressing out any air. Store unused mailers flat in a dry place; damp can weaken the adhesive and soften the paper.

Add a branded sticker or a thank-you card inside to lift the unboxing without adding much weight. A small printed card tucked against the product also helps stop it sliding about inside the mailer. Flat documents that need stiffness rather than padding go in printed C4 envelopes for documents.

Stack the Contents and Measure the Pile

Padded mailers are sized to a stack, not to each item. Lay everything that goes in one order flat in the order you pack it, a notebook, a card and a pen, and measure the length, width and height of the pile. Add 20 mm to the length and width for the padding and the seal, and the mailer size follows. A mailer that is too big lets the contents slide to one end and lose the cushioning; one that is tight will not seal. Tell us the paper colour and whether the mailer goes through a letterbox.

Send the item or mailer size, the colour, the artwork and the quantity, and a custom quote comes by email within one working day; order minimums are worked out for each job and stay low. The free proof shows the print position and the label area. Production takes 4 to 7 working days after approval and delivery to UK mainland addresses is free and tracked in 2 to 3 working days; mailers that arrive damaged or misprinted are reprinted or refunded if reported within 10 days. Orders too thick for an envelope move to the media mailer boxes for books and discs.