A carton label looks like a small sticker, but it is the most-read surface in a shipment. The delivery note gets read once, the packing list a few times; the carton label is read again by every pair of hands between packing and goods-in. This article treats the label as a data-carrying surface rather than a printing material: which fields belong on it, which ones only take up space, how much data a barcode really holds, and whether an SSCC applies to your business.
Note: labelling obligations depend on your product category and on local regulation; confirm your own case against the rules that apply to you or with an adviser.
Who does a carton label talk to?
A carton label has three separate readers, and each of them is looking for something different. The person at the dock gives it two seconds: is this going on the right vehicle, which carton is it, is there anything to be careful about. The handheld terminal or scanner sees only the barcode; for it, the label is one key and nothing more. The customer's receiving system wants to match what it scanned against its own record: which order, which line, how many.
The rest of this article rests on one rule: every field serves one of those three readers. A field that serves none of them clutters the label, slows down reading and forces the information that matters into a smaller font. The label on the carton should not be confused with the paperwork that travels in the vehicle either; for that one, see how a delivery note is issued.
The fields a carton label should carry
First, a distinction: the fields that go into a document are not the fields that go on the carton. For the document side - the list that shows which item sits in which carton - see How to Prepare a Packing List. Here the subject is only what goes on the carton itself. Thinking in five groups makes the decision easier.
- Identity. The carton's own number - the key the barcode carries. It has to be unique inside your business; reusing a number across two shipments means two cartons landing on the same record at goods-in.
- Order link. The order number and line number, plus the customer's own purchase order reference where there is one. The receiving side can only find your carton in its own records through one of those numbers.
- Consignee. Customer name, branch or store code, delivery city and district. A full postal address is not needed on every shipment: if you deliver with your own vehicle or a contracted carrier, the driver already knows the route and what he needs is the store code. Printing the store code large beats printing the full address small when the customer has many branches.
- Contents. Product code, product name or model, the quantity inside and the configuration or variant code where one exists. If two variants of the same product ship in identical boxes, a label without the variant code creates an argument at goods-in.
- Handling. Carton sequence (x/y), weight and handling warnings: fragile, this way up, do not stack. This group is entirely for the person at the dock and says nothing to the scanner - yet when it is missing, the most expensive mistakes come from here.
Why x/y - the carton sequence - is the most critical field
A carton that says 3/5 tells you something on its own: this shipment has five cartons and this is the third. Without that line, a missing carton is noticed days later rather than at handover. By then nobody can say whether it was left in the vehicle, never left the warehouse or fell off on the way; the count does not add up and no one owns the gap.
The rule is simple: x/y is printed once the total carton count is fixed, and it sits on the carton in a readable size. If the total changes, the labels are reprinted - a 4/5 corrected by hand proves nothing during a count.
Product barcode, carton barcode and logistics label are not the same thing
A question that comes up often: can I not just stick the product barcode on the carton as well? No, because the two answer different questions. Barcoding works in three levels.
- Product level. Identifies the individual retail item; in the GS1 world that is a GTIN, usually seen at the till as an EAN-13. This barcode answers "what is this", and every unit of the same product carries the same number.
- Carton / inner case level. Identifies the trade unit that contains a fixed number of items; on cartons it is printed as ITF-14 or GS1-128. It is still answering "what is this and how many".
- Logistics unit level. Identifies a physical unit such as a pallet or a shipping carton, one by one. The SSCC carried by a GS1 logistics label lives at this level and is 18 digits long; two pallets of the same product carry different SSCCs, because the question is no longer "what is this" but "which unit is this".
The distinction in one sentence: a product barcode says what something is, a logistics label says which physical unit it is. Put the product barcode on the carton and the scanner at goods-in cannot tell five identical cartons apart.
Do you actually need an SSCC?
The internet usually answers this with "yes, it is mandatory", and that is misleading. The accurate sentence is: an SSCC is not a government requirement, it is a rule of the GS1 logistics label itself. If you print a GS1 logistics label, the SSCC is the one element that label cannot go without; whether you have to print such a label at all is decided by your customer or by the standard you work under, not by regulation.
In practice there are two cases. You need one: if you supply a supermarket chain or a large retailer, their supplier guide will usually ask for a GS1 logistics label and a matching despatch advice; an export buyer may ask for the same. That requires GS1 membership and a company prefix, because every GS1 key including the SSCC is derived from that prefix. You do not need one: if you ship to your own customers with your own vehicle or a contracted carrier, an internally unique numbering scheme carried in a Code 128 barcode is enough in practice. If nobody outside expects a globally valid key from you, buying one buys you nothing operationally.
The decision in one line: adopt an SSCC because a specific customer or standard asks for it, not because everyone else uses one. And on the day it is asked for you are not starting from zero - if your carton numbers are already unique, the only thing that changes is where the number is derived from.
How much data fits in the barcode?
This is where the urge to print everything hits a wall. The width available to the barcode is fixed - it is whatever the label is wide. The more characters you push into it, the thinner the narrowest bar, the module, becomes. Past a certain point neither the thermal printer prints that thinness cleanly nor the reader separates it reliably.
A concrete example makes it clear. A payload of eight fields, roughly 45 characters, printed as Code 128 across 8.56 cm (about 3.4 in) leaves a module width of about 0.16 mm. The same payload placed in a QR code 1.75 cm (0.7 in) on a side gives a module of about 0.53 mm - the two-dimensional symbol carries the same data far more comfortably. And if you add the QR next to the barcode, the width left for the barcode drops from 8.56 cm to 6.56 cm and the module falls to 0.12 mm: adding one symbol weakens the other.
The rule that follows is the most practical sentence in this article: the barcode does not carry information meant for people. What people read belongs in plain text lines; the barcode carries only the key that finds the record. Squeezing the customer name, the address and the product description into the barcode makes both the barcode and that information unreadable.
Barcode or QR?
The choice depends on what will read the label. If the warehouse uses handheld terminals or keyboard-wedge (HID) fixed readers, a linear barcode is the natural fit: those devices were built for it and read it fast from a distance. If you are thinking of scanning with a phone camera, the QR version of the same payload is the easier option, for the module reason above. Putting both on one label is not free; the arithmetic is a few lines up. Before deciding, print a test label on your own printer and try it with the reader you actually use - print resolution, label stock and reader model decide the outcome together.
Label size, layout and where it goes
The most common carton label size is 100 x 150 mm (4 x 6 in); thermal printers and label rolls are largely sold around it. The GS1 logistics label guideline describes an A6 compact format, 105 x 148 mm, for smaller units. In practice the two are the same size, and that area comfortably holds six or seven text lines plus a barcode.
The layout logic runs top to bottom: human-readable identity at the top (customer, branch, carton sequence), barcode at the bottom. Do not push the barcode against the bottom edge or into a corner; it needs clear space on both sides or the reader cannot find where the symbol starts. The label should not sit over tape, over a corrugation groove or on a folding face, and it should never be wrapped around two surfaces - a bent barcode does not scan.
One rule outranks the rest: only one readable logistics barcode may remain on the carton. The most common mistake on returned or re-shipped cartons is sticking the new label over the old one and leaving part of the old barcode exposed. The scanner will not tell you which one it read; the wrong record simply opens. Remove the old label or cover it completely. How the label is printed in software and how the template is configured is a separate subject: How to print shipping labels
Which rules can bind you?
There is no general rule that dictates what goes on the outside of a shipping carton. Two things decide it instead. First, your contract with the customer or their supplier guide - large retailers publish detailed labelling requirements and treat them as a condition of delivery. Second, regulation specific to your product category: food, chemical substances and mixtures, and dangerous goods carried by road each come with their own labelling and marking rules in most jurisdictions. If you are a GS1 member and print a GS1 logistics label, the standard's own rules apply on top. Confirm the binding rule for your product category against the regulation that applies to you or your customer's supplier guide; this article is not legal advice.
Five carton label mistakes we see most often
- No x/y. A missing carton surfaces when the count fails to add up rather than at handover, and by then nobody can point to where it went.
- Two readable barcodes on one carton. The scanner does not tell you which one it read. The wrong record opens, and the error shows up at reconciliation rather than at the moment it happens.
- Trying to fit every field. The more you put on the label, the narrower the barcode gets and the less reliably it scans - the arithmetic is a few sections up.
- Label stock that does not match the environment. Direct thermal labels darken in a hot or sunlit warehouse and adhesive fails on cold, damp surfaces. Ask where the carton will wait before choosing the stock.
- No branch or store code. The carton reaches the right company at the wrong site. With multi-branch customers this is the most common and the most annoying error, because the goods were delivered - just to the wrong place.
What these five have in common is that none of them is about print quality. All five are about where the data on the label comes from. Building label data in a hand-maintained template is a risk in itself; we covered that in Why Spreadsheets Stop Working for Shipment Tracking.
What changes when the label is generated from the record?
In Smartifie Logistic the label is not typed into a separate template: it is printed from the order record. The label is produced as a 10 x 15 cm page, and you choose what its six lines show for your own company - model, product name, product code, type, HS code, customer name, city, district, address, branch, order number or PO number. Row headings are printed in the local language with the English term underneath, so the receiving side of an export shipment can read the label too.
The carton sequence and package count come from the record itself; the barcode is printed as Code 128 and carries the order number, line, product code, configuration, quantity and package sequence. The same content can optionally be added as a QR next to the barcode. Most importantly, that barcode is scanned back in the same application during loading: which carton of which order it is takes one step to find, and scanning the same carton twice raises a warning.
It runs on the Windows desktop and in a web browser, and the interface is mobile-friendly. The step-by-step use of the label printing screen is covered in How to print shipping labels.