Search engine giant Google was used for 4.8 billion searches during July, according to the latest figures from Nielsen.
Data from the online analyst indicates that of the 7.9 billion search enquiries made during the 31-day period, Google was the engine of choice for 60.2 per cent of them.
This reflects year-on-year growth of three per cent.
Yahoo! Search came in second place, with 1.3 billion searches, or 17.4 per cent of the market for July.
Microsoft took third, with its MSN/Windows Live Search being used for 951 million such enquiries, or 11.9 per cent of the total US market share for the month.
Yahoo! and Microsoft both showed negative year-on-year growth, posting results of -11 per cent and 10 per cent respectively.
In recent days, Nielsen noted that the US users topped its ranking of the ten countries making the most visits to the official site of the Beijing Olympics.
Jon Gibs, vice-president of media analytics at the firm, commented: "Interestingly, traffic from outside of China to the official site tracked closely with medal results at the end of week-one, with visitors from the US, Australia and France in the top three."