A type of exchange-traded fund (ETF) that exclusively invests in bonds. Bond ETFs are very much like bond mutual funds in that they hold a portfolio of bonds and can differ widely in strategies, ranging from U.S. Treasuries to high yields, from long-term to short-term. Bond ETFs trade like stocks and are passively managed.

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A bond ETF trades throughout the day and is therefore more liquid than a mutual fund, which only trades at one price a day according to its net asset value. The drawback to this is that a broker fee is incurred when trading in an ETF, much like when trading a stock.