GS1 Global Location Numbers (GLN) for Ship-To and Dock Locations

A supplier's purchase order arrives with a 13-digit ship-to number, the order management team maps it to "Northgate DC" by name, and the truck is dispatched. The retailer actually meant its new cross-dock two miles away, which shares the same company name but has its own Global Location Number. The load is refused at the gate, re-consigned, and the supplier receives a compliance deduction a month later. Every document in the chain carried the correct number; the supplier's software simply ignored it.

Treating the GS1 Global Location Number (GLN) as the key, and the name and address as descriptive text, prevents that kind of misdelivery. It also lets warehouses identify individual dock doors and staging lanes without inventing private codes that no trading partner understands. This guide explains how the number is built and where it travels, and sets out the rules that decide when a site needs a new one.

• What this guide covers: GLN structure and check digit, party versus location identification, dock-level sub-locations, X12 and GS1-128 usage, and the allocation rules for moves, splits and changes of use.
• What it adds: a worked cost of a wrong ship-to in dollars and rupees, an X12 and label sample, translator validation rules and a rollout checklist.

What a 13-digit GLN encodes and how the check digit is computed

A GLN is always 13 digits: a GS1 Company Prefix licensed to the organisation, a location reference the organisation assigns, and one check digit. The prefix length varies by licence, so software must never try to split a GLN into its parts to infer who owns it. Store and compare the full 13 digits as a string, keeping leading zeros.

The check digit uses the same modulo-10 method as other GS1 keys. Working from the rightmost of the first 12 digits, multiply alternate digits by 3 and 1, add the products, and subtract the total from the next multiple of ten. Validating this digit at entry catches most transposed or mistyped numbers before they reach an order.

GLN check digit (GS1 modulo 10), worked for the example prefix 0614141 + location 00001

Position:  1  2  3  4  5  6  7  8  9 10 11 12
Digit:     0  6  1  4  1  4  1  0  0  0  0  1
Weight:    1  3  1  3  1  3  1  3  1  3  1  3
Product:   0 18  1 12  1 12  1  0  0  0  0  3   -> sum = 48
Check digit = (10 - (48 mod 10)) mod 10 = 2
GLN = 0614141000012

X12 856 ship-to party, GLN qualifier UL (Identification Code Qualifier, element 66):
N1*ST*NORTHGATE CROSS DOCK*UL*0614141000012~

GS1-128 logistic label element strings (AI 410 = ship to / deliver to GLN):
(00)006141410000000012(410)0614141000012

Dock door location label (AI 414 physical location GLN + AI 254 extension):
(414)0614141000029(254)DOOR14

The example prefix 0614141 is the one GS1 uses in its own documentation; the SSCC above is illustrative. In a GS1-128 barcode the element strings are concatenated without brackets, and the brackets appear only in the human-readable line.

Party GLNs versus location GLNs in a buyer's ship-to hierarchy

A GLN answers either "who" or "where", and sometimes both. The GS1 GLN Allocation Rules Standard, Release 3.0.2, defines a party as a legal entity or a function, and a location as physical or digital. A single GLN may identify a combination, but a separate GLN is required wherever separate identification is needed.

Retail and healthcare buyers commonly publish a hierarchy: one GLN for the legal entity that issues purchase orders, one for the accounts payable function that receives invoices, and one for each physical receiving site. The ship-to on an order points at a physical location; the bill-to points at a party. Mixing the two levels is the most common master-data defect in supplier systems.

• Legal entity GLN: the company that contracts and owns the purchase order, typically carried as the buying party.
• Function GLN: a department such as accounts payable or returns, used where the buyer wants invoices or claims routed to it.
• Physical location GLN: a distribution centre, store, cross-dock or plant; a location inside another location can have its own GLN.
• Digital location GLN: an electronic address such as an EDI gateway; the standard's own examples give production and test EDI environments separate GLNs.

GS1 GLN ship-to mapping in an order management master should key on the 13-digit physical location GLN, never on the trading partner's name; the GS1 GLN Allocation Rules Standard Release 3.0.2 section 2.1 separates party GLNs from location GLNs, and one mismatched level can misroute 100% of a site's orders.

Dock doors and staging lanes: separate GLN or extension component

A dock door can be identified two ways: with its own GLN, or with the parent building's GLN plus a GLN extension component carried in Application Identifier (AI) 254. The rule is clear. GLN is mandatory for sub-locations shared across an open value chain, while the extension component may be used internally or between partners who have agreed to it.

AI 254 holds up to 20 characters and is only ever paired with a GLN that identifies a physical location, normally in AI 414. Discontinuing the parent GLN automatically discontinues every extension under it, so a building remodel that changes the site's GLN forces the dock labels to be reissued under the new number.

Carrying ship-to GLNs in X12 N1 segments and GS1-128 labels

In X12 documents the GLN sits in the N1 party segment: N101 names the role, such as ST for ship to or BT for bill to, N102 carries a name, N103 is the qualifier UL for Global Location Number, and N104 holds the 13 digits. Newer X12 releases also define UM for a GLN with an extension component, which must be agreed with the partner before use.

On the physical freight, the GS1-128 logistic label carries the ship-to GLN in AI 410 beside the SSCC in AI 00. When the 856 ship notice, the label and the purchase order all carry the same GLN, the receiving site can confirm destination by scan rather than by reading an address. Our guide to 856 ship notice and SSCC mapping covers the hierarchy that sits beneath that ship-to.

• Purchase order (850): the buyer sends N1*ST with the receiving site's GLN; the supplier stores it on the order line, not just the header.
• Ship notice (856): the supplier echoes the same ship-to GLN; a different value should stop the transmission for review.
• Bill of lading: the location number field on a VICS bill can carry the GLN; our VICS bill of lading guide explains where.
• Invoice (810): the bill-to party is normally a party GLN for the buyer's payables function, not the receiving dock.

EDI ship-to validation for X12 850 and 856 documents should require N103 qualifier UL and a 13-digit N104 that passes the GS1 modulo-10 check digit, then match it to the location master; holding 100% of failures before transmission costs minutes, while a misdelivered truckload costs a reconsignment, a redelivery and often a deduction.

When a moved or repurposed warehouse needs a new GLN

Allocation decisions follow three guiding questions in the GS1 standard: does a stakeholder need to tell the new or changed location apart from the old one, is there a regulatory or liability disclosure need, and is there a substantial supply chain impact? If any one answers yes, a new GLN is required. Physical locations score yes on all three for most changes.

Retired numbers are retired permanently. GS1 changed its rules so that from 1 July 2022 a GLN allocated to a party or location shall not be reallocated to another. Before that date an obsolete GLN could be reused after at least 48 months. A location withdrawn and later reintroduced without changes may use its original GLN again.

Who allocates, who maintains and who may change a location record

The organisation that owns a location allocates its GLN; its trading partners only store it. A supplier must never create a GLN for a customer's warehouse. The supplier's job is to hold the customer's numbers accurately, keep them dated, and stop orders when a number arrives that the master does not recognise. Our guide to logistics master data governance covers change control more broadly; this section applies it to location identifiers.

Incident trace: a ship-to edited instead of replaced

1. 3 March, 10:05: A retailer's onboarding notice announces a new cross-dock with GLN 0614141000036, effective 1 April. The supplier's analyst edits the address on location record CUST-ST-0412, which holds GLN 0614141000012, instead of creating a new record.
2. 28 March, 14:20: Purchase order 4500871 arrives for the old DC with N1*ST GLN 0614141000012; the order system shows the new address and plans the load there.
3. 31 March, 07:45: The truck arrives at the cross-dock, which rejects it because its receiving schedule lists no appointment against GLN 0614141000036.
4. 31 March, 16:30: The carrier re-consigns the load to the old DC and bills redelivery on freight bill 77812-R.
5. Fix: The record is restored, a new record is created for the cross-dock, and the translator now holds any order whose ship-to GLN has no active record.

Cost of a wrong ship-to GLN at a US DC and an Indian modern-trade DC

A single misrouted load costs a reconsignment or return, a second delivery, waiting time and frequently a buyer-imposed charge. The table below uses illustrative figures for one truckload in each market and an annual count of incidents, to show why a translator check is cheap by comparison. Buyer deduction amounts vary by trading partner agreement.

In India, tax documents identify the consignee by GST registration number, address and PIN code rather than by GLN, so a misroute also triggers paperwork. A misroute leaves the movement out of line with the place of delivery declared on the e-way bill, which the tax team must resolve before the goods move again. That is why the ownership table earlier in this guide treats the GLN-to-tax-registration mapping as a master record in its own right.

GS1 US and GS1 India: where GLN demand comes from in each market

GLN usage is driven by trading partners rather than by statute in both countries. In the US, large retailers, grocery wholesalers and healthcare providers ask suppliers to use GLNs on orders, ship notices and labels. In India, GS1 India lists warehouses, hospitals and loading docks among typical GLN locations, but adoption follows buyer requests, and many domestic buyers still identify sites by GSTIN and address alone.

• Allocation in India: GS1 India members with a GS1 Company Prefix can generate GLNs for their own locations in the DataKart portal; organisations without a prefix register individual GLNs through GS1 India's registration form.
• Allocation in the US: companies create GLNs from the GS1 Company Prefix licensed by GS1 US, following the same global allocation rules.
• Food traceability in the US: the FDA food traceability rule in 21 CFR Part 1 Subpart S asks for location descriptions and accepts a "traceability lot code source reference", but its definitions do not name the GLN; treat GLN as a helpful key, not as compliance by itself.
• Digital Link labels: a location can also be expressed as a GS1 Digital Link web address; our GS1 Digital Link QR guide covers how receiving systems parse those addresses.

GLN reuse is prohibited for supply chain location masters: from 1 July 2022 the GS1 General Specifications forbid reallocating a GLN to another party or location, replacing the earlier 48-month waiting period, so a closed warehouse's 13-digit number must stay retired in the master with an end date.

Validation rules a translator can enforce and judgements left to people

Most GLN errors are mechanical and should be stopped by software before an order is accepted or a ship notice leaves. The decisions that need a person are about meaning: whether a new number represents a new site, whether a customer's change of use calls for new routing, and which of two candidate records a free-text address belongs to.

Rolling out GLNs across trading partners without breaking open orders

Introduce GLNs in a sequence that keeps every open order deliverable: load and validate the partner's numbers first, map them to existing locations, run both keys in parallel, and only then make the GLN mandatory. Switching on a hard rejection before the master is complete will stop legitimate orders.

For broader context on location and partner data, see the logistics and supply chain hub. If you are scoping an order, warehouse or EDI platform change that needs GLN validation and dated location masters built in, you can set out your partner list and document flows on our request for proposal page.