Some 7.2 million people tuned in to the three-hour show, hosted by How I Met Your Mother star Neil Patrick Harris.
The telecast came second to an NBA finals game between San Antonio and Miami, watched by 11.6 million.
Kinky Boots dominated the awards, winning best musical as well as five other prizes.
Harris, who made his fourth appearance fronting the event, again drew plaudits for his hosting duties and show-stopping opening number.
"It took Neil Patrick Harris only about three minutes to banish any worries that the fearsome Host Fatigue Syndrome would overtake him and the Tony Awards on Sunday night," said the New York Times.
"He set the bar so high with his introductory flourish that fears of another familiar Tony malady haunted the rest of the CBS broadcast: the dreaded How Do We Top the Opening Number Disease."
The Los Angeles Times also praised the "invaluable, unshakeable" Harris.
The 39-year-old, its critic wrote, "was never too long out of view, and when he was around, he was put to good use".
The event also featured appearances from Tom Hanks, Jake Gyllenhaal, Scarlett Johansson, Sally Field and Mike Tyson.
Last year's Tonys was watched by six million viewers, down from the 6.9 million who saw the show in 2011.
This year's Tony Awards scored its best US TV ratings since 2009, with viewership up 20% from last year's show, according to the CBS network.