I never look, but it's quite a bit this time of year. With high temperatures, low humidity, and wind, our pool can lose up to an inch a day from evaporation. I never checked it because it has auto fill. But if I pull the cover off the auto fill valve, I can hear it running constantly. Between that and 2, 40 foot palms that get water daily, what the wife and I use doesn't matter much. I think last month it was $90.00, or thereabouts.