A rigid packaging container having an integral locking assembly is a rigid U-board having a bottom wall, a first sidewall, and a second sidewall, the bottom wall, the first sidewall and the second sidewall forming a channel. The first and second sidewalls each have a cut therethrough, forming a first channel section and a second channel section. An integral tab in the first sidewall of each of the first channel section and the second channel section is configured to form an integral locking assembly which may be pushed inwardly or pulled outwardly to secure the first channel section at an angle relative to the second channel section.