Depends on which unit you choose, here is the chart for the LX systems: LX500 can scent UP TO 500 square feet of space  LX1200 can scent UP TO 1,200 square feet of space evenly  LX3000 V.2 can scent UP TO 3,500 square feet of space evenly  LX5000 can scent UP TO 5,500 square feet of space evenly LX6000 can scent UP TO 12,000 square feet of space evenly