Your consumer unit needs upgrading if it's more than 25–30 years old, has no RCD protection, uses old rewirable fuses, or has failed an EICR inspection.
🏠Homeowner view
Signs your consumer unit (fuse box) needs replacing: it has old ceramic rewirable fuses instead of modern circuit breakers; there's no RCD protection (no switch with a Test button); it's made of plastic with a split or burnt casing; or an electrician has told you it's unsafe after an inspection. Most consumer units installed before 2000 have inadequate protection by today's standards. An upgrade typically costs £600–1,200 and takes a full day. The new consumer unit will have RCD or RCBO protection on all circuits, meeting current BS 7671 requirements. If you're selling your home, a poor consumer unit will be flagged in a buyer's electrical survey — upgrading before selling can simplify the process. Also, if you're adding an EV charger or solar panels, your existing board may need upgrading anyway to accommodate the new circuits.