A loading tool for loading a collapsible prosthetic heart valve into a delivery device may include a body extending in a longitudinal direction between a proximal end and a distal end, an extension on the distal end of the body, and a slot extending through the extension from a free end of the extension toward the distal end of the body. The body may include a lumen extending between the proximal end and the distal end, the body lumen having a first diameter. The extension may have a lumen coaxial with the body lumen, the extension lumen having a second diameter less than the first diameter so as to define a shelf surface between the proximal end of the body and the free end of the extension.