The firm will be added to the Nasdaq 100 Index on December 21.
Seattle-based Amazon's stock was up 20.5 today after the bell, closing at 242.75 a share. The stock blew past its previous 52-week high of 233.125.
Amazon's market capitalization hit 12.8 billion dollars. The firm's stock has more than doubled in the past three months.
Last month the firm split its stock 3-for-1, sending it soaring by nearly 14 percent. Amazon has seen a fourfold rise in its shares on speculation that the bookseller will capture market share with music and video merchandise.
Bloomberg News contributed to this report