Integrated Business Communications Alliance

IBCA Guidelines for Product ID, Labels and Shipments

Supply Chain Foundation Guide

  1. Introduction Ė Information flow in the supply chain, How to use the documents
  2. Supply Chain Overview and Benefits
  3. Organizing The Labeling Project
  4. Understanding The GS1 System

Label Implementation Guide

  1. Implementing a GS1 System Labeling Project
  2. Implementing Serial Shipping Container Code
  3. Bar Code Print Quality

Contemporary Knowledge:



IBCA Supply Chain Foundation Guide (SCF)

4. Understanding The GS1 System (rev December 2011)

4.1 Introduction

People and organizations communicate better when they both use the same words and numbering systems. In language, standard words are defined in the dictionary. For measurement, the metric system is an international standard. The GS1 System is an internationally accepted method of identifying products, serializing shipping containers and clearly communicating other important business transaction data such as purchase order numbers, expiration dates, lot numbers, etc. in a standard, machine readable (bar code) format.

The GS1 System (Originally referred to as EAN.UCC System with EAN being European Article Numbering and UCC being Uniform Code Council) has been used since 1974 in the food industry but nothing restricts its use in non-food industries. In fact, the GS1 System was originally conceived and developed by members of the electrical products industry for use between manufacturers and distributors. In the United States alone, over 500,000 manufacturers of everything including industrial, general merchandise, food and of course IBCA products are using this product numbering system.

Understanding the concepts of the GS1 System is important to the success of the compliance labeling project, so take your time reading and digesting this chapter before going on to the rest of the book.

This chapter is organized into the following sections:

4.2 Overview of the GS1 System, Sunrise 2005 and GTIN

The objective of the GS1 System is to improve communication between trading partners by establishing a precise but flexible method of uniquely identifying products and package quantity in both human readable and machine readable formats. The GS1 published updated requirements for product numbering called Sunrise 2005. This was necessary to ensure that the system was compatible with domestic and foreign goods. Sunrise 2005 does not change the basic structure of the bar code number. It does require that the data files containing information about the product be redefined as a 14 position numeric field. The file number is called a Global Trade Item Number (GTIN). To simplify things just realize that the carton label always has been 14 digits, so with carton quantities nothing changes. If you have originally assigned 12 digit UPC-A number (now referred to as a GTIN-12) to the consumer unit, that GS1-128 bar code has not changed either. However the GS1 is requiring the data files containing GTIN-12 numbers be expanded to 14 digits by adding two zeros to the leftmost positions of the data field. The bar code does not change. It stays 12 digits long. The following is a brief overview of the GS1 product numbering system.

  • There are rules for assigning Item Reference numbers (GTIN-12) to individual items, called consumer units in GS1 terms. A consumer unit is the lowest saleable unit of sale for a specific product. A single red pen, a 5-Pack, and a 10-Pack of the same red pen are three different consumer units and would each get a different Item Reference number. The Item Reference numbers assigned to "consumer units" are all numeric and the length is determined by the Company Prefix that precedes it. The rules for assigning them are explained later in this chapter under the section titled GTIN-12 and Consumer Units.

  • There are also rules for assigning Item Reference numbers to intermediate packs and shipping containers of consumer units. When identical consumer units are packaged into standard quantities of intermediate packs or shipping containers, GS1 specifies that they should be assigned a new, 14 digit number (GTIN-14). Cases containing 100 individual red pens would be assigned a different 14 digit number than cases containing 10 each, 10-Packs of the same red pen. The rules for assigning these 14 digit numbers are explained later in this chapter in the section title GTIN-14 and Intermediate Packs.

  • There are also rules for assigning unique serial numbers to cartons and shipping containers, like the Package Identification Number (PIN) assigned by common carriers. This system is used in conjunction with EDI (Electronic Data Interchange) to tie the container or pallet to a specific purchase order number. The rules for assigning these are explained later in this chapter in the section titled SSCC and Carton Serial Numbers.

  • There are also rules for communicating secondary information such as purchase order numbers, batch numbers, lot numbers, expiration dates, and other types of data commonly communicated between trading partners. The format for these numbers varies, i.e. not always a specific number of digits or letters, but the rules are precise and allow the information to be encoded in a bar code for fast and accurate data entry. The rules for assigning these numbers are explained later in this chapter in the section titled NOTE: GTIN-14 and Secondary Information.

In addition to defining a standard method of assigning Item Reference numbers, carton serial numbers and identifying secondary information, the GS1 System also specifies which symbologies to use for each different number. The table below describes which numbers to use on different types of items and what symbologies to use.

Item Being Identified

Number Format

Information in the Bar Code


Consumer Unit GTIN-12, 13 Trade Item Identification GTIN-12, 13 or 8
Groupings of individual trade items above unit level (Intermediate, Carton or Pallet) GTIN-14 Trade Item Identification ITF-14 or GS1-128 with Application Identifier of "01"
Transport (Logistic) Unit (Shipping Container) 18 digit Serial Shipping Container Code (SSCC). Serial number uniquely identifying a shipping container, pallet, etc. GS1-128 with an Application Identifier of "00"
Other Length varies but the symbol includes Application Identifiers to designate the type of data in the bar code. Secondary information such as purchase order number, lot number, etc. GS1-128

4.3 GTIN-12 and Consumer Units

The GTIN-12 Global Trade Item Number is a twelve-digit number assigned by a manufacturer to individual "consumer units" in its product catalog. For many, if not most manufacturers, it also becomes the base number for identifying intermediate packs and shipping containers. No alpha characters are allowed in the GS1 System used to identify products or serialized cartons. Catalog numbers containing numbers and letters can still be carried in the inventory file and printed on packages or labels. Different manufacturers offering similar products DO NOT use the same GTIN-12, 13 or 8 number.

A "consumer unit" is the lowest level of packaging for a given product. For example: consider two manufacturers of similar, if not identical, red pens. Both manufacturers offer their red pens in singles and 5-Packs.




Package Description


Manufacturer A

Red Pen

1 Red Pen


Manufacturer A

Red Pen

5-Pack of  Red Pens


Manufacturer B

Red Pen

1 Red Pen


Manufacturer B

Red Pen

5-Pack of Red Pens

In the table above, Items 1 & 3 are similar products in identical package quantities but since they are manufactured by different companies, they would have different GTIN numbers. The GS1 System does not require that all Red pens should have the same item number.

As mentioned earlier, the GS1 has made some changes to the numbering system so it is truly global. One change is the number of digits in the Item level bar code that is read at the point of sale. In North America, this always had been a 12 digit number. However, in other parts of the world the item level bar code is 13 digits. In the future, POS scanners will see more of the 13 digit bar codes. To keep the explanations simple, since most of the companies in the IBCA supply chain are already using the 12 digit item numbers, we will not address the 13 digit numbers here. So, for companies who have assigned and printed GTIN-12 digit numbers, nothing will change.

Items 1 & 2 above are the same product made by the same company but they are different package quantities. In GTIN terms, each of these different package quantities is called a "consumer unit" and would be assigned a different GTIN-12 digit number and, when presented in a data file would have two leading zeros added so it would become a 14 digit GTIN. Since the GS1 is the globally recognized organization we are going to refer to the original UPC-A 12 digit number as the GTIN-12. But it is the same thing. The GTIN-12 is divided into three sections structured as follows:

  • The first section consists of a prefix of digits that is assigned to individual companies by the GS1. No two companies are assigned the same GS1 Company Prefix. To date, approximately 250,000 numbers have been assigned. Instructions for obtaining a GS1 Company Prefix are at the end of this chapter.

  • The second section consists of the Item Reference number that each individual company assigns to its products. The length is determined by the GS1 Company Prefix that precedes it.

In accordance with the GS1 System, manufacturers assign different Item Reference numbers to every consumer unit. Using the red pen example above, an Item Reference number would be assigned to a single red pen and a different Item Reference number to 5-Pack of the same product.

  • The third and last section of the GTIN-12 number is a single calculated check digit that is based on the first eleven digits of the number. The check digit helps intercept transposition errors before they are sent to the computer. See the General GTIN Specification Manual ( for an explanation of the rules for calculating this check digit.

The result is a twelve digit number that uniquely identifies the manufacturer and a specific item or product.


GTIN-12 that could be assigned by the manufacturer to a Red Pen

The GS1 Specification specifies that GTIN-12 data structure (formerly UPC-A) and GTIN-8 (formerly UPC-E) be encoded like this:



Note: GTIN-8 is a special version of the GTIN-12 that reduces the 12 digit number to 8 digits using specific rules. It is used to mark small items and it is only available to companies whose GS1 Company Prefix starts with a zero (0).

Note: The GTIN-13 is fundamentally the same as the GTIN-12. The GTIN-13 contains 13 digits. Companies who have been issued a GS1 Company Prefix do not need to reapply if dealing outside the United States.

Whether the number above is entered from the keyboard or scanned with a bar code scanner, the computer finds the record for the consumer unit of one pen from this specific manufacturer.

4.4 GTIN-14 and Intermediate Packs

GTIN-14 (used in ITF-14, GS1-128 (formerly UCC/EAN-128), Reduced Space Symbols (now called Databar), and Data Matrix bar codes, plus EPCs) primarily relate to 14 digit numeric fields (either numbers and / or bar codes). One digit representing the Indicator digit to indicate packaging level, twelve digits the GS1 Company Prefix and the Item Reference assigned by your company.

As mentioned earlier, if they are both zeros the number would be the global trade item number (GTIN) for the consumer unit. If the leading number is greater than a zero it is still a GTIN but it is also the number that identifies intermediate packs and shipping containers holding standard configurations of consumer units. The 14 digit number, displayed in a bar code is typically called the shipping container code (SCC) but because that sounds so much like the former SSCC we now call it the GTIN-14 because of the expanded definition.

Continuing with the pen example, consumer units of one pen might be boxed by one manufacturer in two standard configurations: cartons containing 500 individual pens and cartons containing 750 individual pens. These are two different package levels for the same consumer unit.

Using the GS1 System, the carton containing 500 would be assigned an indicator digit (package level) of "1" (for example) and the carton containing 750 would be assigned an indicator digit (package level) of "2." (for example) Customers could now order individual pens in cartons containing 500 or 750 individual pens to the carton.

Example of 14 digit GTIN-14

GS1 Company Prefix = 012345

Item Reference = 67890

10012345678902 = 1 carton containing 500 individual pens

20012345678909 = 1 carton containing 750 individual pens

The package level is communicated in the first digit (indicator digit). The indicator digit of "1" doesnít always mean a quantity of 500 consumer units and the indicator digit of "2" doesnít always mean 750 consumer units.

Indicator digits can mean different quantities for different products. The zero (0) following the Indicator digit is automatically added for all North American packages. The original UCC-12 number is the same because it refers to the same consumer unit of one individual pen. The check digit at the end is recalculated based on the previous 13 digits.

The shipping container standard specifies that the GTIN-14 can be encoded in the Interleaved 2 of 5 symbology (ITF-14) or the GS1-128 symbology. Both symbologies are shown below.

Chapter 5: Implementing a GTIN Labeling Project explains how to implement a customer request for both the GTIN-12 and the GTIN-14 described above.

At the option of the trading partners, the GTIN-14 can also be encoded in the GS1-128 Symbology using an Application Identifier (AI) of "01". With this option, the SCC shown above would now be coded as follows using GS1-128.

The number above is interpreted by the computer as the GTIN-14 number. The (01) in the beginning of the number is an application identifier used to signify that the GS1-128 bar code contains the GTIN-14. The check digit at the end is based on the previous 13 digits (does not include the AI of "01"); hence, the GTIN-14 is the same regardless of symbology.

4.5 Carton Serial Numbers

The GS1 System also defines a method of serializing cartons (Serial Shipping Container Code or SSCC), so the contents can be traced to a specific line item (or items) on a specific purchase order. The standard format for serializing cartons and shipping containers is an 18 digit number encoded in GTIN-14 symbology shown in the following illustration. The (00) is the AI for the SSCC. This number may or may not appear on the same label used for product identification and is not generally added to the box or container until the time of shipment.

Serial numbering of cartons provides unique identification. This is important, especially to identify cartons containing variable quantities or non-standard mixtures of product and as a reference number for EDI (Electronic Data Interchange) transactions. When used in conjunction with EDI, serial numbering cartons and shipping containers eliminates the need to physically inspect the contents of every carton. Eliminating this procedure has improved the productivity of some warehouse receiving operations by 100% or more!

The Serial Shipping Container Code (SSCC) is different from the GTIN-14 assigned to intermediate packs and shipping containers of consumer units. The same GTIN-14 is assigned to all identical packaging configurations of the same product. The Serial Shipping Container Code (SSCC) is a unique number assigned to each carton as it is shipped. Because it is unique, it can be used as a reference number tying the contents of a specific carton to information about the shipment including the purchase order(s) it should be applied to, carrier, date of shipment, etc. It is used in conjunction with the EDI 856 Advance Shipping Notice (ASN).

The 18 digit number consists of the following items:

Chapter 6: Implementing a Serial Shipping Container Project explains how to implement a customer request for this numbering system.

4.6 Product ID versus Shipping Labels


4.7 GTIN-14 and Secondary Information

In addition to defining standard methods of identifying products and serializing cartons and shipping containers, the GS1 standard also defines a method of identifying other important types of data with a bar code. For example:

  • Purchase Order Number

  • Production Date

  • Destination Postal Codes

  • Batch Number

  • Lot Number

  • Expiration Date

Bar codes containing secondary information are encoded in the GTIN-14 symbology and include prefix codes, called Application Identifiers (AI's), to designate the type of data they contain. For example, the serial shipping container code contains the AI of "00" to indicate that the bar code contains a serial shipping container code. A bar code containing a purchase order number would start with the AI of "400." Bar codes containing batch numbers start with the AI of "10."

Application identifiers can be used by the computer system to automatically read many bar codes and place them in the proper fields in a database. AIís will be used extensively with some ANSI MH10.8 labels (the basis for the label found on the shipping container).

4.8 Getting a GS1 Company Prefix

When a GTIN number is needed (whether the company manufactures or packages a product), companies should contact the GS1 to get a uniquely assigned Company Prefix. GS1 assigns Company Prefixes and maintains a database assuring that no other company is assigned the same number. Applicants should contact GS1 and request an application form. Their address and phone number is shown below:

The GS1 US Customer Service Team provides a single point of contact for all member support activities. As the "front line" of support for GS1 US members, Customer Service Representatives answer questions about a variety of GS1 US related issues, such as, the process of obtaining a GS1 Company Prefix (used in developing a UPC-A bar code), GS1 System standards, educational programs, and education products as well as a variety of general interest questions. The GS1 US Customer Service Team can be reached Monday through Friday from 8:00 AM to 6:00 PM EST.

4.9 Summary of the GS1 System

The GS1 System assigns company prefix numbers from which the company defines different product identification numbers to their individual "trade items". Consumer units are assigned a 12-digit number. Packaging levels above the consumer unit are assigned a 14-digit number.

Consumer units are defined as the smallest unit intended to be sold to the ultimate end user. A single red pen and a 5-count pack of red pens are considered different consumer units.

Trade items above the consumer unit may be intermediate packs, cartons, packs containing multiple consumer units or standard mixtures of consumer units. A carton containing 4 reams of paper is an intermediate pack. A carton containing 12 of the same reams of paper is another intermediate pack. These are two different inventory keeping units or trade items.

The standard also defines how to assign serial numbers to shipping containers. This GTIN-14 Serial Shipping Container Code (SSCC) uniquely identifies shipping containers and provides a method of linking the physical carton or shipping container to information about its contents. The SSCC is an 18-digit number preceded by AI "00".

Finally, the standard also defines a method of identifying secondary information such as purchase order numbers, expiration dates, etc. either for internal uses or on the ANSI MH10.8 label.

By using a standardized numbering system, manufacturers donít need to maintain a different item number file for each customer that buys that product. Distributors and retailers can use the GS1 System to place orders, automate receiving and maintain inventory counts by scanning the GTIN-12 bar code on individual items and the GTIN-14 (ITF-14 or SSCC 18 digits) bar code on cases and cartons.

Using the GS1 System with Existing Internal Numbers

If desired for internal purposes, individual companies may also continue to use their own proprietary number for any purpose other than communicating with an independent trading partner. This is done by using an "alternate" part number field in the inventory or part number database. This enables the use of either GTIN-12 (UPC-A) or existing proprietary number.

4.10 Additional Reading on the GS1 System

  • GTIN-12 (UPC-A) Symbol Specification

  • Application Standard for Shipping Container Codes

  • GTIN-14 Application Identifier Standard

  • GS1 Symbol Placement Guidelines

  • Apparel Guidelines: Format and Symbol Placement

  • GS1 Quality Specification for the GTIN Printed Symbol

  • General GTIN Specification

  • GS1 Solutions Center

These materials are available from the GS1at 1-937.435.3870 or visit their web site at



IBCA  Phone: 215.489.1722  Email:

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