Bond whose interest is free of federal, state, or local tax in the state of the issuer. It is typically a municipal bond of estate or county agency. For example, a New York City resident does not pay federal, state, or city tax on the interest received from a New York City obligation. It is triple tax-free though this is not necessarily the case with other states. The return on a tax-exempt bond is equivalent to a higher return on a taxable corporate bond because of the tax savings. The dollar advantage of a tax-exempt security increases as the tax rate rises. Assume a taxpayer in the 31% tax bracket receives 5% on a tax-exempt bond. The equivalent taxable yield on a corporate bond is 7.2%(5%/.69).