I am living in Michigan (state income tax) and my spouse is living in Washington (no state income tax). We are interested in investing in municipal bonds. From my understanding, in order to take advantage of the tax-free coupon payments, a Michigan resident would need to buy a Michigan municipal bonds. A Washington-resident, on the other hand, would be able to buy any states' bonds. In this case, if my spouse buys municipal bonds under his name, would he be free to purchase bonds from any state? Or would he need to buy Michigan bonds? We currently file federal/state taxes jointly in Michigan, but my spouse who lives in Washington is filing as a non-resident.