Perforated leather upholstery is standard, and heated front seats are optional. The monochromatic interior features chrome accents and dark woodgrain trim. Standard steering-wheel controls operate the stereo. With the 60/40-split rear seats folded, the Rainier has 80.1 cubic feet of storage space.

The instrument panel features green-needle gauges that are reminiscent of those in the Rendezvous. Dual-zone automatic climate control is standard, and the Rainier is equipped with GM's OnStar communication system. A navigation system, DVD video system and XM Satellite Radio are optional.