Abstract: An extendable boat trailer has a wheeled chassis adapted to be secured to a towing vehicle, and a boat supporting cradle movable rearwardly and forwardly on the chassis. The cradle includes a rear section which is engaged by a low friction conveyor in the form of rollers on the chassis for guiding the rearward and forward movement on the chassis, and a forward section extending upwardly and forwardly relative to the rear section. The forward section includes retaining members thereon that are cooperable with rollers on the chassis for engaging the rollers on the chassis when the cradle has been fully extended. A removable towing hitch is separable from the trailer, and the trailer includes only one winch.