While it’s not harmful to let your pool pump run continuously, it’s usually not necessary and can lead to higher energy costs. A properly sized pump should be able to circulate the entire volume of pool water in about 8 to 12 hours. Therefore, running your pool pump for around half of the day is often sufficient for most residential pools. However, many factors can affect this, including the size of your pool, the pump’s capacity, and the pool’s usage.