It depends on so many factors, for me. If I get bored, really bored, I'll rebuild a coil instead of trying to clean it. I've had the same coil last for over a month before, but I usually rebuild between 1 & 4 times a month, depending on how dirty the coil is, if flavor is lingering even after cleaning & dry burning, if my coil is totally warped beyond salvation (had that happen a while back because I pulled the cap off my IGO too hard, with wet hands, and it flew across the kitchen and the coil got squished), etc. I rewick at least once a day, usually more, because I switch flavors so much (and I use cotton because I hate the taste of silica). I'm also a chain vaper of 100% VG, so my coils tend to get gunky pretty quick, especially with my really thick or really dark juices.