Understanding Global Location Numbers (GLNs): A Complete Guide

Introduction to Global Location Numbers

A Global Location Number (GLN) functions as a unique identifier used to recognize and distinguish locations and legal entities within business operations. These numbers consist of three key components: a GS1 Company Prefix, a Location Reference, and a Check Digit.

GLNs serve as essential reference codes that connect additional information about companies or their specific locations. They replace lengthy names and addresses, making them particularly valuable for automated operations requiring speed and accuracy, such as Electronic Data Interchange (EDI), where GLNs identify various parties including business partners and physical locations.

How GLNs Are Structured and Obtained

The nonprofit organization GS1 configures GLNs and manages their allocation. This organization issues application guidelines, handles business instances, and oversees maintenance of the GLN system.

Once you've acquired a GLN for your business by approaching the GS1 organization, your company becomes ready to participate in EDI and benefit from electronic exchange systems.

Applications of Global Location Numbers

GLNs identify various entities across business operations:

GLNs also identify geographical locations including physical sites such as production facilities, distribution centers, stores, or even specific locations within sites, like dock doors or storage areas.

Additionally, GLNs can represent digital sites such as EDI gateways or ERP systems.

For legal entities, GLNs can represent entire companies, subsidiaries, or specific departments like healthcare divisions within larger organizations.

In terms of operational entities, GLNs identify specific divisions within companies, such as finance departments, purchasing teams, or specialized units like hospitals.

The GLN is necessary for using the Global Data Synchronization Network (GDSN) and various e-commerce processes. This worldwide identification system ensures that information encoded in a GLN—whether in a barcode or an Electronic Product Code (EPC)—matches electronic documents shared between business partners.

Benefits of Using Global Location Numbers

Implementing GLNs for identifying divisions, functional groups, and physical locations offers numerous advantages:

GLNs are recognized globally, eliminating the need for trading partners to assign proprietary numbers to ensure uniqueness.

Using GLNs saves both money and time as they move efficiently through supply chains.

These numbers help fulfill business requirements across various locations, from cargo areas to government facilities to circuit boards within routers.

Companies can use GLNs for general divisions at one location and for automated stations such as bank ATMs or automated dispensers.

GLNs allow businesses to determine locations both inside and outside their organization in ways that are:

• Straightforward: GLNs are simple data types with fairness checks that facilitate easy processing and transmission

• Exclusive: No two GLNs are identical

• Cross-sector: GLNs identify any site for any organization regardless of its operations worldwide

GLN Encoding Methods

Global Location Numbers can be encoded in various formats for different technologies and systems:

GS1-128 barcodes encode GLNs and often appear on shipping labels to represent information about transported products, including details about transaction parties such as manufacturers, buyers, or suppliers.

EPC-enabled RFID tags incorporate Electronic Product Codes within Radio Frequency Identification technology. These tags track products throughout supply chains. GLNs embedded in RFID tags allow systems to automatically identify locations or transaction parties without manual scanning.

GS1 DataMatrix functions as a 2D matrix (similar to QR codes) storing large amounts of data in small spaces. This coding works well for smaller items with limited space and can encode GLNs to help identify products or locations.

GLNs in EPC Information Services

EPCIS provides a standard for sharing information about product movements and status throughout supply chains. When used in this system, GLNs specifically identify where particular events (shipments, deliveries, storage) occur. This ensures global visibility and consistent identity for locations in supply chains. Essentially, GLNs function as "addresses" within EPCIS, precisely indicating where supply chain events happened, which proves valuable for tracking and traceability.

GLNs Versus Internal Numbering Systems

While businesses may develop unique internal methods and systems to code locations within their operational areas, this approach—though seemingly simple—creates problems when information flows between different companies' computer systems:

Duplication issues arise when multiple business partners use identical location codes for their internal sites, compromising uniqueness.

Complexity challenges emerge as internal codes adopt different compositions and formats, making application programming increasingly complicated and resulting in costlier changes.

Significance problems develop when location codes with linked information become difficult to manage as coding structures evolve to incorporate new values.

Significance Problems with Location Codes: Explained Simply

Imagine you're organizing your toy collection. You decide to create a code system where:

• Code starts with "B" for bedroom toys

• Code starts with "L" for living room toys

• Code starts with "K" for kitchen toys

So you might label your teddy bear as "B001" because it belongs in the bedroom.

Now here's where the "significance problem" happens:

One day, you decide to move your teddy bear to the living room. The code "B001" now doesn't make sense anymore because "B" means bedroom, but the toy isn't in the bedroom! You'd need to create a whole new code like "L001" for your teddy bear.

This is exactly what happens with business location codes that have "significance" built into them:

When a company creates codes where the letters or numbers have specific meanings (like "W" for warehouse or "S" for store), they run into problems when things change. If a warehouse becomes a store, or if a department moves to a different building, the code doesn't match reality anymore.

With GLNs, the numbers don't contain any built-in meaning about the location - they're just unique identifiers. So if a location changes its purpose or function, you don't need a new GLN - you just update the information linked to that GLN in your database.

This makes GLNs much more flexible and easier to maintain over time, especially as businesses grow and change!

Permanence of Global Location Numbers

A GLN links directly to a specific location. When changes occur at a site, those responsible for the GLN must update the corresponding details in linked records.

If a GLN is discontinued, it remains valid for at least three years before potential reassignment. During this period, trading partners can locate old location number references and remove them from their files. GS1 must reissue GLNs for reuse.

Major Retailer Requirements for GLNs

Major retailers often require suppliers to include Global Location Numbers in specific EDI transaction segments. For example, some retailers request GLN information within the N1 ST segment element 04 (with appropriate qualifiers in element 03) on all EDI 810 Invoices and non-purchase order invoices.

These numbers typically appear within N1 ST segment element 04, N1 BY segment element 04, or SDQ segments of EDI 850 Purchase Orders. Suppliers may locate GLN numbers for stores, warehouses, and organizations when using AS2.

Future of GLNs in Business

As GLNs become more widely adopted, businesses will find it increasingly easier to share information, simplify e-commerce operations, and improve productivity. The standardized approach to location identification creates a foundation for more efficient supply chain operations and business transactions globally.

Conclusion

Global Location Numbers represent a fundamental component of modern business identification systems. By providing unique, standardized identifiers for physical locations, legal entities, and digital systems, GLNs facilitate smoother transactions and improved supply chain visibility. As businesses continue to digitize operations, understanding and implementing GLNs becomes increasingly important for companies of all sizes across industries.