The value of the tech company's stock reached the $2,050.50 mark for the first time, after a run-up that saw the share price double in less than a year.
Launched in 1994 by founder Jeff Bezos, Amazon's revenue now tops the economic outputs of Hungary, Kuwait and other countries.
Last month, Applebecame the first $1 trillion publicly listed U.S. company, after a decadelong rise in its stock price fueled by its ubiquitous iPhone.
Those trillion-dollar valuations are bigger than the combined market capitalization of Exxon Mobil, Procter & Gamble and AT&T. Apple and Amazon each account for about 4 percent of the value of the entire S&P 500.
Here's how Amazon's market cap compares to the rest of the stocks in the S&P 500: