Most homeowners should clean their septic tank at least once every 3-5 years. However, the way that you use your septic system will impact how frequently you should schedule a cleaning service. You may need to clean your septic tank more often if: You have a large household: According to the Environmental Protection Agency, the average American uses 82 gallons of water each day. Larger households will produce more waste and therefore need more frequent cleaning services.  You flush improper items down the drain: From flushable wipes to grease, there are a lot of substances that your septic tank will not be able to break down. The more these items go down the drain, the more likely you are to encounter issues with your septic that require cleaning or even repairs. Your septic tank is small or old: Smaller septic tanks will fill up faster and need to be emptied out more frequently than larger units. Additionally, older systems should be cleaned more often to prevent issues that could lead to a breakdown.