Single Wall Cardboard Boxes

Single wall corrugated boxes, supplied flat in trade packs for UK sellers, online retailers and trade counters. Also called single wall cardboard boxes, single wall cartons or 3-ply boxes — the same product under different names. These are the everyday dispatch boxes: the ones you reach for on most orders, rather than the ones you keep back for awkward jobs. Bought wholesale in trade packs by UK sellers, packers and fulfillment operations.

What single wall means, and when it's enough

Single wall is 3-ply corrugated board: one layer of fluting between two flat liners. The fluting is what does the work — the arched profile resists compression and absorbs impact, while the liners hold it in shape and give you a printable surface.

That construction gives you rigidity and impact resistance at the lowest weight and cost of any corrugated format. It handles loads up to roughly 10–15kg, depending on the box and how the weight sits inside it.

For apparel, books, cosmetics, small parts, lightweight electronics, documents and general non-fragile goods, single wall is the correct specification — and anything heavier-duty is money spent on board you don't need.

Where it isn't enough: glassware, ceramics, anything you've had damage claims on, or boxes that will be stacked more than three high in storage. Those want the second flute layer of 5-ply construction — see double wall cardboard boxes.

The honest test isn't weight, it's consequence. A 12kg box of paperbacks is fine in single wall. A 4kg box of mugs is not.

Specifications and terminology

Corrugated board is described in a shorthand that isn't obvious if you don't buy it every week. The terms that matter when comparing suppliers:

Ply — the number of paper layers. Single wall is 3-ply: liner, flute, liner. Double wall is 5-ply: liner, flute, liner, flute, liner. More ply means more compression resistance and more weight.

Flute — the corrugated middle layer. Profiles are lettered by height, with taller flutes giving better cushioning and shorter ones giving a smoother print surface and better stacking strength. Most general-purpose single wall uses a mid-height profile as the sensible compromise.

Liner — the flat outer and inner sheets. Kraft liner is the brown, stronger, virgin-content option; test liner uses more recycled fibre. Kraft takes labels and print more cleanly.

Edge Crush Test (ECT) — how much force the board withstands on its edge before crushing. This is the number that predicts stacking performance in a warehouse or a courier cage, and it's the most useful single figure when comparing two boxes that look identical.

Bursting strength — resistance to puncture. Relevant if your goods are dense or have corners.

Flat-packed — supplied unassembled and folded, so a pallet of boxes takes a fraction of the storage space. Assembled with standard tape; no tooling required.

If you're specifying packaging for the first time, ECT and ply are the two that will actually change your damage rate. The rest is detail.

Choosing a size

Sizes, codes and pack quantities are in the table below. Three things decide which one you want.

Measure the product packed, not flat, then add 20–30mm per side. Void fill exists to stop movement, not to fill a box you shouldn't have bought. A box that needs more than a handful of fill is the wrong size.

Match the shape, not just the volume. A cube and an oblong of the same capacity behave very differently around a folded garment or a stack of books. Look at the proportions, not only the litres.

Size down before you size up. Couriers charge on the greater of actual or volumetric weight, so a box one size too large costs you on every parcel even when it's light. The smaller box is usually cheaper twice over — less board, and less billed volume. Our cardboard boxes page works that calculation through properly.

Common jobs, and what usually works

Clothing and textiles. Single wall throughout. Fabric is forgiving and light, so the constraint is volumetric weight rather than protection — go as small as the folded garment allows.

Books and print. Single wall handles weight well but not corner impact. If you ship hardbacks or higher-value editions, consider a book wrap instead, which folds to the depth of the contents.

Cosmetics and beauty. Usually single wall with light void fill. If the contents are glass, treat it as fragile and step up to double wall.

Small electronics and accessories. Single wall is normally right, but keep the box snug — movement inside the carton causes more damage claims than the board grade does.

Homeware and gifts. Depends entirely on fragility rather than weight. A 3kg ceramic item needs more protection than a 10kg textile order.

Subscription and multi-line orders. Standardise on two sizes rather than matching a box to every order. The picking time saved outweighs the small amount of extra void fill.

Buying by the pack

Supplied flat-packed in trade packs, with price breaks as pack quantities increase. Prices exclude VAT.

The common mistake here is ordering one pack of every size. You end up with capital tied up in slow-moving formats and a picking bench nobody can navigate. Most operations dispatch the bulk of their orders from two sizes — find yours, concentrate the volume there, and the break price does the rest.

These are made on our own corrugated plant. You're buying from the manufacturer rather than from a reseller who bought them from one, which is where the trade price comes from — there's no margin stacked in between.

The range is growing, and it won't cover every job. If the size you need isn't in the table, we make bespoke — send us the dimensions rather than sizing up and paying to ship air.

Practical detail

Assembled with standard tape, no special tooling. The kraft outer takes labels, direct print and barcodes cleanly. Fully recyclable, and compatible with Royal Mail, Parcelforce, Evri, DPD, Yodel, UPS and DHL.

Not sure which sizes suit your product mix? Send us your dimensions and typical weights and we'll work through it with you.

Delivery and returns

Next-day dispatch on UK mainland orders, with a £75 minimum order. Full terms on our delivery and returns pages.