If you’re interested in investing in tax-free municipal bonds, you may wonder if they’re really free of taxes. While the investment generally provides tax-free interest on the federal (and possibly state) level, there may be tax consequences. Here’s how the rules work. Purchasing a bond  If you buy a tax-exempt bond for its face amount, either on the initial offering or in the market, there are no immediate tax consequences. If you buy such a bond between interest payment dates, you’ll have to pay the seller any interest accrued since the last interest payment date. This amount is treated as a capital investment and is deducted from the next interest payment as a return of capital. Interest excluded from income  In general, interest received on a tax-free municipal bond...