The time it takes to empty a septic tank can vary depending on the size of the tank and the complexity of the job, but most professional services can complete the task within 1 to 2 hours. This includes the time needed to locate and access the tank, pump out the contents, inspect the tank for any signs of damage, and clean up the area. Larger tanks or tanks that haven’t been emptied in a long time may take longer to service. It’s always a good idea to schedule enough time for the job to be done thoroughly.