Market risk - Perhaps the most significant risk associated with ETFs is market risk. This risk is defined by the day-to-day fluctuations associated with any portfolio and defined by the perception of investors. Market risks include, but are not limited to: fiscal and monetary policy decisions, general economic conditions, geopolitical uncertainty, inflation or deflation concerns, commodity price fluctuations, and currency valuations.
Liquidity risk - All ETFs are purchased on an exchange with a bid and offer. In some cases, the number of shares trading in any given day may not easily support a sale or purchase at an efficient price relative to the underlying net asset value. In other cases where volume is high and market velocity rapid, ETFs have decoupled from their underlying net asset value. Also, many bond ETFs seem to trade at a premium or discount to net asset value.
Concentration risk - The degree of diversification in any particular ETF varies significantly and the underlying portfolio should be closely examined to see what level of diversification a fund may offer. Some ETFs are characterized by a heavy concentration in just a few stocks, particularly sector ETFs that are capitalization weighted indexes.
Interest rate risk - As interest rates rise and fall over time, these changes have a direct effect on the value of ETFs that are investing in bonds. As interest rates rise, the value of an ETF invested in bonds should be expected to fall. In a declining interest rate environment, the value of a bond ETF investment should rise. Longer-term bonds are more sensitive to changes in future inflation expectations than are short-term bonds.
Foreign investment risk - Many ETFs are organized to hold non-U.S.-based stocks. Investing in a basket of international stocks poses additional risks to shareholders, including currency risk, liquidity risk, geopolitical considerations, newly established and emergent markets, and less-stringent accounting methods.
Manager risk - Despite ETF transparency, you must understand the risks embedded in any underlying strategy. Otherwise, the use of ETFs may be substantially more risky than selecting very broad based mutual funds such as balanced funds.
Commission costs - In most cases, the purchase or sale of an ETF involves a commission. There may be an alternative to the ETF that is similarly invested that may be purchased without a commission in the form of a no-load index fund. This risk is most relevant for smaller accounts where the transaction costs as a percentage of your principal can significantly diminish the return on your portfolio.