Scan & Generate
What Is an SSCC? Pallet Labels Explained
A retailer has told you that every pallet needs an SSCC on a GS1 logistics label, and the paperwork assumes you already know what that means. Here is the whole thing in plain English: what the 18 digits are, how to build one, and how to read the label a supplier sends you.
Somewhere in a supplier agreement there is usually a line like this: "All logistic units must carry a GS1 logistics label bearing a unique SSCC." It is written as though everyone already knows what that means. Most people do not, and the official answer is a 500-page specification.
This is the plain-English version. What an SSCC actually is, how the eighteen digits are put together, how to work out the last one yourself, and how to read the label on a pallet that has just arrived at your door.
What Is an SSCC?
SSCC stands for Serial Shipping Container Code. It is an 18-digit number that identifies one specific logistic unit — this pallet, this carton, this roll cage — for as long as that unit exists.
The important word is specific. Two identical pallets, built the same morning, holding the same product, get two different SSCCs. The number does not describe what is on the pallet. It is a licence plate for the pallet itself.
That is what makes the rest of the supply chain work. When a distribution centre scans an SSCC at goods-in, it is not learning "this is a pallet of shampoo". It is matching that physical object against a despatch advice sent electronically hours earlier — which already lists what is on it, how many, and which purchase order it belongs to. One scan reconciles a lorry-load. This is what makes cross-docking and automated receiving possible at all.
SSCC vs GTIN: what versus which one
| GTIN (AI 01) | SSCC (AI 00) | |
|---|---|---|
| Answers | What is this? | Which one is this? |
| Identifies | A product line | A single physical unit |
| Length | 8, 12, 13 or 14 digits | Always 18 digits |
| Shared | Every jar on the shelf shares one | Never — each is used once |
| Typically on | The retail item | The pallet or shipping carton |
If you are still getting your bearings across the wider family of codes, our guide to the different types of barcodes sets out where each one is used, and barcode formats compared covers how they differ technically.
How the 18 Digits Are Built
An SSCC has four parts, and only one of them is yours to invent freely:
| Part | Length | Who decides it |
|---|---|---|
| Extension digit | 1 | You — any digit 0–9, used to widen your own numbering capacity |
| GS1 Company Prefix | 7–10 | GS1, when you join |
| Serial reference | Fills the gap | You — a sequence you control |
| Check digit | 1 | Arithmetic — calculated, never chosen |
The rule that ties it together: the company prefix and the serial reference always add up to 16 digits. A longer prefix leaves you a shorter serial. A company with a 7-digit prefix gets a 9-digit serial reference — a billion numbers per extension digit, which is why almost nobody ever runs out.
A worked example
Take a company with the GS1 Company Prefix 5012345, issuing its 678,901,234th unit, using extension digit 3:
- Extension digit:
3 - Company prefix:
5012345 - Serial reference:
678901234
Strung together that gives seventeen digits — 30501234567890123 — and the eighteenth is calculated from them.
How the check digit is calculated
The same modulo-10 arithmetic used by every GS1 key. Working from the rightmost of the seventeen digits, multiply alternately by 3 and 1, add everything up, and take whatever is needed to reach the next multiple of ten.
For 30501234567890123:
| Digit | 3 | 0 | 5 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Weight | 3 | 1 | 3 | 1 | 3 | 1 | 3 | 1 | 3 | 1 | 3 | 1 | 3 | 1 | 3 | 1 | 3 |
| Product | 9 | 0 | 15 | 0 | 3 | 2 | 9 | 4 | 15 | 6 | 21 | 8 | 27 | 0 | 3 | 2 | 9 |
The products total 133. The next multiple of ten is 140. 140 − 133 = 7, so the check digit is 7 and the complete SSCC is:
305012345678901237
Because the weights alternate, transposing two adjacent digits changes the total — which is exactly the mistake a human retyping a number makes most often. You can check any GS1 key against this arithmetic with our barcode check digit validator.
The one-year rule
An SSCC is reusable, but not quickly. The GS1 General Specifications require that an SSCC is not reallocated within one year of the shipment date to a trading partner, and individual sectors or regulators may demand longer. In practice most companies never reuse one at all: the numbering space is enormous, and a duplicate SSCC arriving at a distribution centre is a genuinely expensive problem to unpick.
How to Read a GS1 Logistics Label
The label itself is standardised, which is why a pallet from a supplier in one country is readable at a depot in another. It is built from three stacked blocks, top to bottom:
- Top — free format. Your logo, the supplier and customer names, addresses, anything not encoded in a barcode.
- Middle — human-readable text. The same data as the barcodes below, spelled out with labels like "GTIN", "BATCH/LOT", "BEST BEFORE", so a person can read it when a scanner fails.
- Bottom — the barcodes. The SSCC always sits in its own barcode at the bottom of the label, alone, as the last thing on it.
Those blocks are often described in terms of who knows the data and when: a carrier section, a supplier section and a customer section. The practical consequence is that a label may be printed in stages — the supplier's data first, the carrier's routing information added later — which is why you sometimes see two labels, or one printed over another.
What is actually encoded
The SSCC is the only mandatory element on a GS1 logistics label. Everything else is there because a trading partner asked for it. Common additions:
| AI | Meaning | Why it is there |
|---|---|---|
| (00) | SSCC | Identifies this unit. Mandatory. |
| (02) | GTIN of the items contained | Used on a single-product pallet, always with (37) |
| (37) | Count of contained items | How many of that GTIN are on the unit |
| (10) | Batch or lot number | Recall scope and traceability |
| (17) | Expiry / best-before date | Stock rotation at the depot |
| (400) | Customer's purchase order number | Matches the delivery to the order |
| (403) | Routing code | Carrier sortation |
Note that a mixed pallet uses no (02) or (37) — there is no single GTIN to state. In that case the SSCC alone carries the identity, and the contents live in the electronic despatch advice.
A full label, decoded
A single-product pallet might encode this, written the way humans write it:
(00)305012345678901237(02)09506000134352(17)270131(37)24(10)LOT2609
Which reads as:
- (00) This is pallet
305012345678901237 - (02) containing product
09506000134352 - (17) best before 31 January 2027
- (37) 24 of them
- (10) from batch
LOT2609
The brackets are a human convention only — they are never encoded in the barcode. A scanner returns the digits run together, with an invisible separator after each variable-length field. If you have a raw scan in front of you and want it broken into labelled fields, paste it into our GS1 barcode decoder, which validates the SSCC check digit while it goes.
The Barcode Itself: GS1-128
The barcode carrying all this is GS1-128. It uses the Code 128 symbology, but it is not the same thing as a plain Code 128. The difference is an FNC1 character in the first position, which flags the contents as structured GS1 data organised by Application Identifiers rather than as free text. It is the same mechanism that distinguishes a GS1 DataMatrix from an ordinary Data Matrix — a distinction covered in our guide to what GS1 DataMatrix is.
GS1-128 is a linear barcode, so it grows longer as you add fields. That is why a logistics label often carries two or three separate GS1-128 bars stacked up rather than one very wide one.
Print specification
A pallet label gets scanned at arm's length by a handheld gun, sometimes on a moving forklift, often after a week in a cold store. The print specification reflects that:
| Property | Guideline |
|---|---|
| X-dimension (narrowest bar) | 0.495 mm recommended |
| Minimum bar height | 32 mm on a pallet label |
| Quiet zone | At least 10× the X-dimension, each side |
| Label size | A6 (105 × 148 mm) for SSCC only; A5 (148 × 210 mm) when trade item data is added |
| Placement | Two adjacent sides of the pallet, so it is readable from either approach |
The quiet zone is the one most often lost. A label designed to the millimetre and then printed onto stock that is 3 mm too narrow will fail at goods-in for a reason nobody can see by looking at it. The same principle applies to 2D codes — our QR code size guide covers it from the other direction.
Why not a QR code?
Because the reading equipment already exists and works. Distribution centres are full of laser scanners that read linear barcodes at distance and at angle; 2D codes need an imager. That is changing — GS1 Sunrise 2027 is pushing 2D codes onto retail items, and GS1 has published guidance for 2D symbols on logistics labels — but the transition on pallets is behind the one at the checkout, and GS1-128 remains what most trading partners specify today.
Where It Usually Goes Wrong
- Reusing a serial too soon. The one-year rule exists because two live pallets sharing a number make an unresolvable mismatch at goods-in.
- Padding the prefix wrongly. The prefix and serial reference together are 16 digits. Losing a leading zero somewhere in a spreadsheet produces a 17-digit SSCC that no scanner will accept.
- Typing the check digit by hand. It is calculated, not chosen. Copy it from the generator, or compute it.
- Encoding the brackets. "(00)" is how the number is written on paper. The barcode contains
00followed by the digits. - Putting the SSCC anywhere but last. Convention places it in its own barcode at the bottom of the label. Depot staff and automated readers both look there first.
- One label per pallet. Two sides, adjacent, so the unit can be read whichever way the forklift approaches.
- Assuming a supplier's label is correct. Scan and check it on arrival. A check digit failure is cheap to catch at the door and expensive to catch in the system a week later.
Frequently Asked Questions
What does SSCC stand for?
Serial Shipping Container Code. It is an 18-digit GS1 identification key that identifies one individual logistic unit — a pallet, carton, or roll cage — rather than a type of product.
How many digits is an SSCC?
Always exactly 18: one extension digit, a GS1 Company Prefix of 7 to 10 digits, a serial reference filling the remainder, and one check digit. The company prefix and serial reference always total 16 digits between them.
Do I need to be a GS1 member to create an SSCC?
Yes. The middle of the number is your GS1 Company Prefix, which is issued to you when you join a GS1 member organisation. You cannot invent one, because the prefix is what makes your numbers globally unique and traceable back to your company.
What is the difference between an SSCC and a GTIN?
A GTIN identifies a product line — every identical jar on a shelf shares one. An SSCC identifies a single physical shipping unit and is never shared. A pallet label commonly carries both: the SSCC for the pallet, and a GTIN stating what is on it.
Can an SSCC be reused?
Not within one year of the shipment date, under the GS1 General Specifications, and some sectors and regulators require longer. Most companies simply never reuse one, because the available numbering space is far larger than they will ever need.
What is the difference between GS1-128 and Code 128?
GS1-128 uses the Code 128 symbology with an FNC1 character in the first position. That character flags the data as structured GS1 content organised by Application Identifiers. A plain Code 128 can carry any text a company chooses, with no standard structure.
Can I scan a pallet label with a phone?
Yes. A phone camera reads GS1-128 perfectly well at close range, which is enough for spot checks, receiving small deliveries, or verifying a label before a pallet ships. Dedicated handheld scanners still win for high-volume receiving, where read distance and one-handed operation matter more than anything else.
Does the SSCC tell me what is on the pallet?
No, and that is the design. The SSCC is only an identifier. What is on the unit comes either from other Application Identifiers on the same label, such as (02) and (37) on a single-product pallet, or from the electronic despatch advice the SSCC is matched against.
The Short Version
An SSCC is a licence plate for a pallet: 18 digits, unique to that one physical unit, built from an extension digit, your GS1 Company Prefix, a serial reference you control, and a calculated check digit. It travels in a GS1-128 barcode at the bottom of a standardised logistics label, on its own, and its whole job is to let one scan at goods-in match a physical object to a message that arrived before it did.
If you are on the receiving end of these labels, the useful habit is the same one that applies to every GS1 code: stop treating the number as opaque. Scan it, split it into fields, and check the check digit. Almost every problem an SSCC causes is visible the moment the string is broken into its parts.