A cabinet for an electrical switchboard includes a supporting base and a frame mounted on the supporting base. The supporting base includes a base element having a lower wall configured to rest on a bearing surface, and a first lateral wall and a second lateral wall which protrude transversally from the lower wall and face each other. The base element includes a first upper wall protruding from an upper end of the first lateral wall towards the second lateral wall, a second upper wall protruding from an upper end of the second lateral wall towards the first lateral wall, so as to extend over at least a portion of the first upper wall. The base element also includes a coupling mechanism which couples the first and second upper walls to each other for supporting a corresponding portion of the frame.