Postal Boxes

Peel and seal postal boxes and mailing boxes for UK online sellers and small businesses. One-piece FEFCO 0427 construction with a self-adhesive strip, so a packed box needs no tape at all. Made on our own corrugated plant, supplied flat in trade packs. See our full range of postal boxes, or peel and seal mailing boxes for one-touch packing.

What 0427 means, and why it's the standard

FEFCO 0427 is the industry code for the classic one-piece postal box: a single die-cut sheet that folds into a tray with tuck-in side wings and a front flap that locks into a slot.

It's the most widely used postal format in the UK for good reasons. One piece means nothing to lose and nothing to assemble wrongly. The locking flap holds the box closed before the adhesive is even peeled. And because it ships completely flat, a pallet holds a great many more of these than of any glued format.

The peel-and-seal strip runs along the closing flap. Pull the liner, press down, done — no tape, no dispenser, no plastic on the parcel.

Which of our two postal ranges you need

We stock two, and the difference is assembly speed rather than protection.

These boxes are one-piece 0427. You fold the base yourself. Simplest format, lowest cost per box, and completely adequate for anyone packing tens of parcels a day rather than hundreds.

Our ecommerce postal boxes have a crash lock base — pre-glued, so the bottom locks itself in one movement. Three or four seconds saved per parcel, which only pays for itself at volume.

If you pack fewer than a few hundred parcels a week, buy these. The crash lock is a labour-saving feature, and labour you aren't spending isn't a saving.

Postage: parcels, not Large Letters

All three sizes here are depth boxes at 50mm or more, and Royal Mail's Large Letter band caps at 25mm. These post as Small Parcel — 45 × 35 × 16cm, up to 2kg.

If you need Large Letter rates, your product must be under 25mm packed, and that's a letterbox box rather than anything on this page.

Volumetric weight is where the money is here. Most couriers price on the greater of actual weight and length × width × height divided by a divisor. A box one size too big can cost more to send than a heavier parcel in the right box, every single time.

Choosing a size

Dimensions and pack quantities are in the table below.

Measure the product packed, including any inner protection, then take the closest size above it. Sizing up "for safety" adds void, and void adds volumetric weight and movement — the two things that cost you money and break things.

Two sizes usually cover a catalogue — one for the standard order, one for the outliers. Concentrating volume gets you further up the price break than spreading it thinly.

What these suit

Small business and marketplace sellers posting daily

Clothing, accessories and giftware

Books, stationery and printed matter with some bulk

Cosmetics, candles and homeware

Spare parts, tools and components

Anyone moving off tape-sealed boxes for speed or sustainability

Why buy from us

We're part of a manufacturing group and the corrugated board is made in-house rather than bought in and marked up. On a commodity format like 0427 — which every supplier in the country sells — the only real differences are price, availability and lead time, and buying direct addresses all three.

Over 100,000 square feet of warehousing sits behind the range, so a size you standardise on stays available.

Practical detail

Micro-flute corrugated, supplied flat and pre-scored, with a peel-and-seal strip on the closing flap. Fully recyclable, and because it needs no tape the customer can put the whole box in the paper recycling without stripping anything off it.

Need a size that isn't listed, or a printed outer? Tell us what you're sending — bespoke is a quote, not a problem.

Delivery and returns

Order by 2pm, Monday to Friday, for same-day dispatch. Free UK mainland delivery in 1–2 working days, with a £75 minimum order. Full terms on our delivery and returns pages.