SSCC-18 and the GS1 Logistics Label: How to Label Pallets Correctly
Written by Tomasz Lichosik
Ready to generate barcodes?
Create high-quality labels in seconds.
Somewhere in your customer's routing guide there is a sentence like this: "Each pallet must carry a GS1 logistics label with a unique SSCC." If that sentence sent you searching, this guide covers everything the receiving dock will actually check: what the SSCC is, how its 18 digits are constructed, how the label is laid out, and the handful of mistakes that get pallets quarantined or refused.
What an SSCC actually is
The Serial Shipping Container Code (SSCC) is an 18-digit number that identifies one specific logistic unit — a pallet, a roll cage, a parcel, a container. Think of it as a licence plate: it says nothing about what is inside, it only says this exact unit and no other.
That distinction matters. A GTIN answers "what product is this?" — every identical carton shares the same one. An SSCC answers "which shipment unit is this?" — two pallets with identical contents still get two different SSCCs.
On the label, the SSCC is carried in a GS1-128 barcode with Application Identifier (00) in front of it.
Anatomy of the 18 digits
An SSCC is built from four parts:
| Part | Length | Purpose |
|---|---|---|
| Extension digit | 1 digit | Free digit (0–9) chosen by you — multiplies your serial capacity by ten |
| GS1 Company Prefix | 4–12 digits | Issued by your national GS1 organisation; identifies your company |
| Serial reference | fills to 17 digits | Your own running number for the unit |
| Check digit | 1 digit | Modulo-10 check computed over the first 17 digits |
Two practical consequences follow. First, you cannot invent an SSCC — the company prefix comes from GS1 membership, exactly as with GTINs. If you don't have one yet, start with our guide to the GS1 Company Prefix. Second, the shorter your company prefix, the more serial numbers you have; even the smallest allocation gives you tens of thousands per extension digit, which resets the "will we run out?" worry for most businesses.
The check digit uses the same modulo-10 algorithm as the GTIN check digit. Don't compute it by hand — a wrong final digit is one of the most common reasons an otherwise perfect label fails verification.
The GS1 logistics label layout
The standard label (usually A6, 105 × 148 mm, or A5 for more data) reads top to bottom in three zones:
- Free-format zone — your company name, logo, ship-to address. No rules beyond legibility.
- Text zone — the human-readable interpretation of every barcode on the label, so a person can key the data in if a scanner fails.
- Barcode zone — the GS1-128 symbols. The SSCC (00) always goes in the bottom-most barcode.
A homogeneous pallet often carries a second GS1-128 above the SSCC with the contents: (02) the GTIN of the cartons inside, (37) how many there are, plus (10) batch and (17) expiry where traceability demands them. The rules for what those identifiers mean are covered in our GS1-128 vs Code 128 guide.
Placement is standardised too: the bottom edge of the barcode should sit between 400 and 800 mm above the base of the pallet, at least 50 mm in from any vertical edge, and GS1 recommends labelling two adjacent sides — one short, one long — so the code is scannable however the pallet is racked.
Why receiving docks insist on it
The SSCC is the key that links the physical pallet to the electronic paperwork. Before the truck arrives, you send a despatch advice (EDI DESADV, or "ASN") that lists each SSCC and its contents. At the dock, one scan of the licence plate tells the receiver's system everything on the pallet — no counting, no manual matching against the delivery note. That is why a wrong or duplicate SSCC is treated as seriously as a wrong quantity: it breaks the automated receipt for the whole unit.
Assigning SSCCs without getting burned
- One unit, one SSCC. Every pallet gets a fresh number, even if ten pallets are identical. Rebuild a pallet after packing? New SSCC.
- Never reuse too soon. GS1 requires a minimum of 12 months before a serial reference may be reassigned; many industries (pharma in particular) expect far longer. Sequential assignment from a counter you persist is the simple, safe pattern.
- Don't encode meaning into the serial. Warehouse, line or date logic embedded in the digits always runs out of room. The serial is just a serial; the meaning lives in your systems and the despatch advice.
Four mistakes that get pallets rejected
- Reused or duplicated SSCCs — usually a label reprint that operators stick on a second pallet. The receiver's system sees the same unit arriving twice.
- Wrong check digit — hand-typed numbers or spreadsheet formulas that silently drop a leading zero. Always generate, never transcribe.
- AI formatting errors — encoding the literal parentheses into the bars, or omitting the FNC1 character so
00...scans as plain text instead of an SSCC. Any GS1-aware verifier catches this instantly. - Print quality and size — the SSCC barcode needs an X-dimension of roughly 0.5–0.94 mm and bars at least 32 mm tall. Shrinking it to fit a small label, or printing on a worn thermal head, produces a code that scans on your desk and fails on a moving forklift. Our thermal printing guide covers the hardware side.
The short version
An SSCC-18 is a unique licence plate for one logistic unit: extension digit + GS1 Company Prefix + serial + check digit, encoded in GS1-128 with AI (00) at the bottom of a three-zone logistics label. Get the prefix from GS1, assign serials sequentially, never reuse them within a year, and let software compute the check digit.
When you need the labels themselves, BarcodeReady's bulk barcode generator turns a pasted list or CSV into a print-ready PDF — including Code 128 symbols on Avery sheets or DYMO rolls.