The invention relates to a unit comprising a refillable bottle for dispensing a fluid product and a source (15) of product intended for the filling of said refillable bottle, said source comprising a reservoir (18) provided with a device for dispensing, said refillable bottle comprising a reservoir (2) and a device (10) for dispensing, said refillable bottle provided with a valve (14) for filling the reservoir (2), with the opening of the source (15) provided with a socket (23) for the reversible connection of the device for dispensing by putting into sealed communication the means for supplying said device with the source reservoir (18), said socket being arranged, after disconnection of the device for dispensing, to allow for the connection of the refillable bottle by actuating the opening of the valve (14) in order to put into sealed communication the reservoirs (2, 18) for the purposes of filling.