An image forming apparatus and method for determining a toner level and providing a notification are provided. The method of operating an image forming apparatus includes counting a number of times a lower toner hopper receives toner from an in-situ refillable upper toner hopper, calculating an estimate of toner volume transferred from the lower toner hopper to a surface of a photosensitive drum, determining an amount of toner consumed from the in-situ refillable upper toner hopper based on the number of times the lower toner hopper receives toner from the in-situ refillable upper toner hopper and the estimate of toner volume transferred from the lower toner hopper to the surface of the photosensitive drum, and generating an upper toner hopper refill notification when the amount of toner consumed from the in-situ refillable upper toner hopper is determined to exceed a threshold value.