Yes, some munis can be subject to this tax. While most munis pay interest that’s free from federal income taxes, some may pay income subject to the alternative minimum tax, or the AMT. It’s a little more complicated than we have space for here, but this is absolutely why you need to talk to your tax professional or financial planner before making a move into munis. In any case, beware of "private activity muni bonds."
Don’t forget to ladder: “Laddering” is a portfolio structuring term. To ladder bonds means that you are buying them with maturities occurring at regular intervals, so when they mature, you’ll have money to reinvest at those same regular intervals. Laddering also offers you some portfolio diversification across many parameters including, time, municipality, interest rate, and debt quality.