A meter socket, load center combination apparatus is disclosed. The meter socket, load center combination apparatus has an enclosure having a meter socket section with a meter socket configured to receive a utility meter, a load center section having a panelboard with a plurality of locations configured to receive circuit interface devices, and a cross-bus connection section extending between first and second sides of the enclosure, the cross bus connection section having one or more side openings configured to allow electrical connection to one or more cross bus bars, and a main circuit breaker coupled between the panelboard and the meter socket. Methods of assembling power distribution systems and electrical distribution systems including the meter socket, load center combination apparatus are disclosed, as are other aspects.