I enjoyed your article about premium muni bonds generally having a higher effective yield, but I’d like to point out what I believe is an equally offsetting downside. As we know, the interest payments by the premium bond are higher compared to the equivalent par bond (i.e. compensation for having paid an upfront premium). Therefore, the state income tax on these bonds (from states other than one’s home state; in my case, Idaho) will be higher because there is no mechanism that I know of for deducting the premium paid for the bonds. So, without finding a legitimate way to deduct the premium for state income tax purposes, I estimate that my additional taxes to Idaho on an out-of-state muni bond purchased with a 6% premium eats up most of the 0.5% higher yield you cite in your article (i.e. 7.8% Idaho income tax x 6% premium = 0.47%).
E.H., Idaho