Can you name the current tallest building in the United States without looking it up?. A lot of us have probably had a vague sort of notion about the tallest buildings. For something like forty years the Empire State Building was the tallest not only in the U.S. but in the entire world. The ESB barely makes the top ten in the United States now. Then, for a while it was the Sears Tower in Chicago (now #3 and called the Willis Tower).