The euro is currently the second most commonly held reserve currency, comprising about a quarter of allocated holdings.

After World War II and the rebuilding of the German economy, the German Deutsche Mark gained the status of the second most important reserve currency after the US dollar. When the euro was introduced on 1 January 1999, replacing the Mark, French franc and ten other European currencies, it inherited the status of a major reserve currency from the Mark. Since then, its contribution to official reserves has risen continually as banks seek to diversify their reserves, and trade in the eurozone continues to expand.

Former U.S. Federal Reserve Chairman Alan Greenspan said in September 2007 that the euro could replace the U.S. dollar as the world's primary reserve currency. It was "absolutely conceivable that the euro will replace the US dollar as reserve currency, or will be traded as an equally important reserve currency."

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