We are told by many customers who have the Sharper Image Ionic Breeze Air Purifier that finding replacement light bulbs are hard to find. We stock them and ship them out to customers daily. The bulbs are a Philips UV G15 T8 light bulb. The Sharper Image manual recommends that you change these bulbs every 12 months. The bulb may still be working but from the tests that Sharper Image ran, they tested the units to be optimally working when the bulb is replaced every year. You can purchase the bulbs HERE.