Abstract: A telescoping seating system has a plurality of row assemblies which may be extended for use or retracted to nested relation for storage. Each row assembly includes a pair of floor wheel channels. A post is mounted to each wheel channel; and a deck (which may include a riser beam) is connected between the tops of the posts. The invention enables the understructure configuration of all row assemblies to be similar. In a preferred form, the posts extend upwardly and they are inclined inwardly so that all posts on each side of the structure are parallel, and the connection between the posts and decks are in vertical alignment on each side. Thus, all row assemblies have a uniform center span. End cantilever spans beyond the posts are also equal for all row assemblies.