Most importers treat packaging as an afterthought: the product is agreed, and then someone asks what box it goes in. That order of events costs money in three places at once — container fill, damage rate and customs. Packaging is a development project with its own samples and approvals, running alongside the product. This article is for companies producing branded or custom goods in China from roughly 1,000 units per order.
The three levels, plus the pallet
- Retail packaging — the box the end customer sees: print, finish, inserts, hang tab or shelf orientation.
- Inner carton — an intermediate box, typically 6–24 retail units. It protects, and it becomes the natural wholesale unit.
- Master carton — the export box: what gets weighed, measured, labelled and stacked.
- Palletisation — how master cartons stack, whether pallets are used at all, and whether they need ISPM-15 heat treatment for your market.
Each level needs its own specification, its own sample and its own approval, exactly like the product itself — see the technical spec sheet for a Chinese factory.
Why packaging decides your cost per unit
A container is a fixed volume. Master carton dimensions determine how many units fit inside it, and a carton two centimetres too tall can cost you an entire layer per container. Working backwards from container internal dimensions to carton size — rather than forwards from "what box fits the product" — routinely recovers 5–15% of shipping cost per unit. The arithmetic sits inside landed cost of a China import, and for dense or heavy goods it interacts with weight limits, as shown in container loading calculations.
For air freight the same logic bites harder: you pay on volumetric weight, so every unnecessary centimetre of cardboard is billed on every shipment. The trade-off between modes is in sea versus air freight from China.
Materials and strength
- Corrugated flute. B flute is thin and rigid for retail; C flute gives more cushioning; BC double wall is for heavy or stacked goods.
- Board strength. Specify it by a measurable standard — edge crush or bursting strength — not as "strong carton."
- Moisture. A sea container sweats. For anything corrosion-prone or paper-based, specify desiccant, moisture-barrier bags or shrink wrapping, and say how much.
- Inserts. EPE foam, moulded pulp, blister or die-cut cardboard — chosen by fragility and by the retail impression you want.
- Sealing. Tape width, sealing pattern, strapping for heavy cartons.
The tests that matter
Ask for these on real filled cartons, not empty ones, and get photographs or video:
- Drop test. Corner, edge and face drops from a stated height, on the packed master carton.
- Compression test. How much load the carton takes before deforming — this decides how high it can be stacked in a container and in a warehouse.
- Transit or vibration test. Simulates the road leg, which is where most damage actually happens.
- Moisture exposure, where relevant.
A packed sample carton should also go through the pilot run as it will actually ship, sealed and labelled — that is when packaging failures show up while they are still cheap.
Labelling and barcodes
- Retail barcode (EAN-13 or UPC-A), from your own GS1 prefix, printed at a scannable size and contrast, and test-scanned before mass printing.
- Carton labels: your SKU, quantity, net and gross weight, dimensions, carton number of total.
- Shipping marks agreed with your forwarder, on two sides minimum.
- Country of origin marking — "Made in China" where required, in the right place and permanence, because customs treats it as a compliance matter, not a design one.
- Language requirements of the destination market for consumer-facing text.
- Handling symbols — fragile, this way up, stacking limit.
Getting origin marking or mandatory labelling wrong is a customs problem, not a cosmetic one, and it surfaces at the worst moment — see import documents from China.
Print and colour approval
Colours drift between screen, proof and production run. Ask for a physical print proof before the full run, specify Pantone references rather than "dark blue," and approve a physically produced carton — not a PDF. Where the print is part of the brand, treat the approved carton as a reference sample in the same way as the golden sample for the product.
Common and expensive mistakes
- Designing the retail box first and the master carton second. The container should drive the dimensions, not the graphic design.
- Approving artwork on screen. Screens do not print.
- Skipping the drop test because the product feels sturdy. It is the carton that fails, not the product.
- Ignoring moisture on a 35-day sea leg through the tropics.
- Leaving barcodes untested. A batch that will not scan at the retailer is a batch you cannot sell.
Packaging is the only part of your order that every single link in the chain touches — the factory, the loader, the port, the carrier, customs, the warehouse and the customer. It is also the part most often designed last.
Developing packaging as part of the order
We specify all three packaging levels with the factory, work carton dimensions backwards from container fill, run drop and compression tests on filled cartons, verify barcodes and origin marking against the destination market, and approve print physically. Seven years, 3,500+ deliveries and 340+ verified suppliers — real projects in our case studies.
See custom packaging and private label manufacturing, or start with product sourcing.
