While interest on municipal bonds is tax free for federal income tax purposes, gain or loss on the sale of the bonds must be reported. The loss is treated as a capital loss, which is deductible within capital loss rules. This means the capital loss can fully offset capital gains. Any excess losses can then offset ordinary income up to $3,000 ($1,500 for those who are married filing separately). If the loss is not fully used up, it is carried forward to the following year and applied in the same way.
A mutual-fund distribution allocated to gains realized on the sale of fund portfolio assets. You report the distribution as long-term capital gain even if you held the fund shares short term.