A step platform for use with a stepladder having front and back legs. The front leg has a plurality of steps. The step platform includes a tread portion connected to a locking portion. The tread portion has a front portion configured to rest upon a selected one of the steps and a back portion configured to extend from the front portion toward the back leg beyond the selected step. The locking portion extends alongside a front portion of the selected step and at least partially wraps around a lower edge of the front portion.