A belt tensioner includes a support housing at least in part defining a spring cavity and an arm pivotally attached to the support housing. A spring is located in the spring cavity and is operatively connected to the arm and the support housing to bias the arm about a pivot axis toward an unloaded position relative to the support housing. A damping member includes a hub and deflectable, force-applying elements that are connected to and spaced apart about a periphery of the hub. The force-applying elements are biased toward a contact surface of the arm to apply a frictional force between the contact surface and the force-applying elements to impede rotation of the arm relative to the support housing.