Tuck Top Mailer Boxes Made to Your Inside Size

What is a tuck top mailer box?

A tuck top mailer box is cut and creased from one sheet of corrugated board. The base, the back wall and the lid are a single piece, so there is no separate lid to lose. Two dust flaps fold in from the sides, the lid comes over the top, and the front edge of the lid rolls down and tucks behind the front wall.

Because the front wall is doubled by that rolled lip, the box feels firm where a courier bag feels soft. You can open and close it a few times without wearing the crease, which helps when you pack in batches and want to check an order twice. It sits in our range of mailer box styles beside ear lock, side loading and end open designs.

How do you close a tuck top mailer?

Closing takes a few seconds once you have done it twice. The order matters, because the side flaps have to sit under the lid rather than over it.

1. Fold the two side dust flaps inwards so they lie flat against the contents.
2. Bring the lid over from the back wall until the front lip hangs down over the front panel.
3. Push the lip down and in so it slides between the front wall and the folded dust flaps.
4. Run a thumb along the front crease so the lid sits flush, then add a sticker if the parcel will be handled roughly.

The tuck holds on friction alone, so a sticker over the lip is a nice touch rather than a necessity. Many sellers use a printed label there as a seal and a signature at the same time, and it tears cleanly when the customer lifts the lid.

Who posts in tuck top mailer boxes?

Anyone sending a single order to a single customer. The style suits goods that lie flat or stack neatly, where the box sets the tone of the parcel before the product is seen.

• Clothing brands posting a folded T-shirt or a pair of socks with a thank-you card.
• Skincare and candle sellers sending a two or three item set in a fitted insert.
• Stationery shops sending notebooks, pens and prints that must arrive uncreased.
• Bakers posting biscuits and brownies in a tray that sits inside the box.
• Gift shops building a birthday or Mother's Day bundle around one box size.

What size tuck top mailer box do I need?

Measure the item, or the stack of items, at its longest, widest and tallest point. Add 3 to 5 mm a side for clearance so the lid closes without bowing. That gives the inside size we quote, written as length x width x depth.

The Small Parcel limit is 450 x 350 x 160 mm, so most tuck top sizes sit well inside it. Check the current band limits before you order, and remember that the outside size is what the band measures, not the inside. Our guide to measuring a mailer box walks through it with a ruler and a notepad.

E-flute or B-flute for a tuck top mailer?

E-flute is 1.5 mm thick with a fine flute. It takes sharp print, creases cleanly and keeps the box slim, which matters when you are trying to stay under a band limit by a few millimetres.

B-flute is 3 mm thick with a larger flute. It gives thicker walls for dense or awkward items and a softer feel in the hand. For most tuck top jobs under 300 mm we suggest E-flute; move to B-flute when the box is bigger or the contents push on the walls. We cover the difference in E-flute versus B-flute for mailer boxes.

Printing outside, inside, or both

Brown kraft board prints well in one or two colours, and a white underprint lets full colour sit bright on the brown. White-lined board gives a clean base for photographic artwork or pale tones that would sink into kraft.

The inside of the lid is the panel the customer sees first when the box opens. A pattern, a short message or a single logo there costs little extra on the same print pass. Plain, one colour, two colour and full colour are all available, outside only or on both faces, and a matt or gloss varnish finishes the outer face.

Do tuck top mailer boxes need an insert?

Not for soft goods like clothing or a wrapped bar of soap. A sheet of tissue and the right clearance is enough to stop the contents sliding about.

For bottles, jars or a set that must arrive in a certain order, a die-cut board insert holds each item in its own aperture. Dividers split a box into two or three bays and paper void fill takes up spare space. If the insert is the main point of the job, start with our insert fitted mailer boxes instead.

How tuck top mailers arrive and store

Boxes are delivered flat, creased and bundled, with tracked UK mainland delivery free in 2 to 3 working days. A bundle of flat blanks is only as thick as the board, so a few hundred sit on one shelf rather than filling a room.

Keep them flat and dry until you need them. Folded boxes stacked in a corner take space and the creases soften over weeks, so fold as you pack and keep the bundle strapped until then.

Mistakes to avoid with tuck top mailers

• Measuring the outside of an old box and sending that as the inside size.
• Forgetting the clearance, so the lid bows and the tuck will not hold.
• Printing a dark solid on kraft without a white underprint and expecting it to look bright.
• Choosing a depth of 26 mm when 24 mm would have kept the box in Large Letter.
• Placing the address label area on the lid lip where it tears on opening.
• Approving a proof on a phone screen without checking the text at full size.

How to order tuck top mailer boxes

Send the inside size, the board, the quantity and a note on print, and we quote in writing within one working day, from £0.25 a box. Artwork can follow later; a free proof is made before anything is printed and nothing goes on press until you approve it.

Production takes 4 to 6 working days after approval. If a misprint or damage turns up, tell us within 10 days with photos and we reprint or refund. Ask for a written quote for your size or send a WhatsApp message to +44 7578 382054 with the three measurements.