Every narrowboat kept, used or moored on the connected inland waterways needs a current licence: from the Canal & River Trust on most canals, or the Environment Agency on the rivers it manages. The licence sits alongside two other requirements: a valid Boat Safety Scheme certificate, renewed periodically, and third-party boat insurance. Licence fees are calculated by the boat's length and width, so there's no single flat figure: "Licences are now calculated by length and width (also known as 'beam')" (Canal & River Trust, boat licensing FAQs). Check the Trust directly for current rates before budgeting. You choose between a home-mooring licence, tied to a fixed berth, or a continuous-cruising licence for a boat with no permanent mooring. Cruising without a valid licence isn't a grey area, see what happens if you don't have one. Once the paperwork's sorted, the boat's name is worth celebrating properly: see our narrowboat gifts.
The licence turns up again the day you start buying her, because it is one of the running costs a sale advert never mentions. For the fee itself, broken down, read what a narrowboat licence costs. Two of the Trust's own conditions are worth quoting: "All types and sizes of boats with or without a motor need a licence", and "Before you buy a boat licence, you'll need a valid BSS certificate or exemption" (Canal & River Trust, licence your boat). A Boat Safety Scheme certification, once issued, "will be valid for four years" (Boat Safety Scheme).
