Homeowners typically spend several hundred to several thousand dollars for distribution box work in septic systems, depending on system size, material, and installation complexity. The main cost drivers are the number of boxes, trenching, backfill, and permit requirements. Cost estimates below use. Replacing a septic system distribution box is no easy task. Even the most skilled DIY homeowners should hire a plumber to tackle the job, which can cost anywhere from $550 to $1,800. Labor makes up the largest portion of the cost to replace a septic distribution box, running as high as $1,200 for. Septic systems are an essential part of rural and suburban sanitation, designed to treat wastewater from homes that are not connected to municipal sewer systems. A critical component of this system is the distribution box (D-box), which plays a vital role in directing effluent from the septic tank. If you are standing in a half-finished warehouse or staring at a flickering panel in a residential complex, you've probably asked yourself: how much is a distribution box anyway? It is the silent heart of any building, pumping electricity to every corner, yet we only think about it when the lights. In the United States, buyers typically pay for a distribution box (D-box) as part of septic system upgrades or repairs. A distribution box serves as a crucial component in electrical installations, housing circuit breakers, fuses, and other protective devices that ensure safe power distribution.