A fabric case for an electronic device may include a back panel having a periphery and a sidewall that extends around the periphery. The back panel and the sidewall may be joined monolithically or may be joined using seams. A monolithic fabric case may be formed by knitting rows of loops to create a sidewall, knitting rows of loops to create a back panel, and joining the loops of the sidewall with the loops of the back panel as the back panel is being knitted. A fabric case with seams may be formed by attaching a fabric sidewall to a fabric back panel using a seam such as a chain stitch. The sidewall may be a seamless tube of fabric that extends continuously around the back panel. The seamless tube may be folded to create interior and exterior walls. A stiffener may be interposed between the interior and exterior walls.