I usually only change out the coil when I want to try something different. Rarely is there a time that the coil is replaced because of need. Have a few coils that have been vaping great for a couple months now, with no need of rebuilding. I get several weeks out of the wick before needing to change and dry burn the coil. Much depends on the build, wick material, and wicking method. My through the coil builds require more frequent maintenance than around the coil wicks for some reason.