The GS1 Reduced Space Symbology (RSS) family contains three linear symbologies (RSS-14, RSS Limited and RSS Expanded) to be used with the GS1 system. The use of the symbology is intended to comply with the GS1 application guidelines as defined in the GS1 General Specifications.

RSS-14 encodes the full 14-digit GS1 item identification in a linear symbol that can be scanned omnidirectionally by suitably programmed point-of-sale scanners. RSS Limited encodes a 14-digit GS1 item ?identification with Indicator digits of zero or one in a linear symbol for use on small items that will not be scanned at the point-of-sale. RSS Expanded encodes GS1 item identification plus supplementary AI element strings such as weight and 'best before' date in a linear symbol that can be scanned omnidirectionally by suitably programmed point-of-sale scanners.

RSS-14 Stacked is a variation of the RSS-14 symbology that is stacked in two rows and is used when the normal symbol would be too wide for the application. It comes in two versions, a truncated version used for small item marking applications and a taller omnidirectional version which is designed to be read by omnidirectional scanners. RSS Expanded can also be printed in multiple rows as a stacked symbol.

Any member of the RSS family can be printed as a stand-alone linear symbol or as part of an EAN.UCC Composite symbol with an accompanying two-dimensional component printed above the RSS linear component.

GS1 RSS bar code symbols are intended for encoding identification numbers and data supplementary to the identification. The administration of the numbering system by EAN and UCC ensures that identification codes assigned to particular items are unique worldwide and that they and the associated supplementary data are defined in a consistent way. The major benefit for the users of the GS1 system is the availability of uniquely defined identification codes and supplementary data formats for use in their trading transactions.

ISO/IEC 24724:2006 defines the requirements for the RSS symbology family. It specifies the characteristics of the RSS symbology family, data character encodation, symbol formats, dimensions, print quality requirements, error detection, and decoding algorithms.

For EAN.UCC Composite symbols, ISO/IEC 24723 defines the two-dimensional component.