Its stock surged during morning trading on the Nasdaq, reaching the milestone when its share price hit $2,050.50 per share.
It crossed the line at 16:40 BST before falling back slightly.
However it was tech giant Apple that was named as the first publicly listed United States company to be valued at $1,000,000,000,000, on 2 August. The combined value of both companies is equal to roughly 10 percent of USA gross domestic product.More news: Extortion plot led to recovery of 'Oz' ruby slippers
Amazon and Apple are now worth more than the economies of countries such as Turkey and Switzerland.
By October 2009 it had risen to $100 and the stock hit $1,000 for the first time on May 30, 2017. "Now that it has several high-margin revenue streams, we're seeing those doubts subside".
Amazon's financial and business successes even pushed the founder and CEO, Jeff Bezos, right to the top of Forbes' billionaires list this year. Amazon also operates the world's largest cloud-computing platform, Amazon Web Services, which rents computing power to a huge number of organizatons. It is now worth about $1.1 trillion.
Bezos is now worth over $165 billion, well ahead of runner-up Bill Gates, whose wealth clocks in at just over $98 billion, according to Bloomberg. Bezos brought home an annual salary of $81,840 in 2017, according to regulatory filings.
'The company continues to experiment with new products and push into new geographies.