A multi-drawer file cabinet having an upper cabinet that may be stacked on top of a lower file cabinet is provided. The lower cabinet includes a top surface having a peripheral edge with a first perimeter. The upper cabinet includes a base with a sidewall. The sidewall has a peripheral edge with a second perimeter. The second perimeter is larger than the first perimeter so that the sidewall fits around the peripheral edge of the top surface of the first cabinet. The cabinets include an extendable drawer assembly having a pair of slide members slidably positioned between a pair of outer tracks formed in a casing and tracks formed in a drawer frame. Furthermore, a locking assembly is associated with a recess in the casing and a ledge of a drawer head to allow the drawer assembly to remain in a locked position even if the cabinet sustains fire damage.