They never trailed and led by 25 but overcame a late rally by the Tribe (6-5) and a technical foul on coach Roy Williams to earn their fourth straight win.
Daniel Dixon scored a career-high 20 points and Marcus Thornton added 17 for William & Mary.
The Tribe closed within single digits only once in the second half, with Dixon's 3-pointer from the corner made it 68-59 with 6 minutes left.
Paige followed with a three-point play, then hit two free throws on the next trip downcourt to push the lead to 14.
Britt then hit 3s on consecutive possessions about a minute later to make it 79-60, and the Tar Heels continued to pull away for their eighth straight win in the series.
North Carolina - which entered 9-0 when scoring more than 70 and 0-3 when scoring 70 or fewer - became the first team this season to reach that mark against the Tribe.
Tokoto was coming off a three-point effort three nights earlier against UAB and reached double figures for the first time since scoring 19 on Dec. 7 against East Carolina.
It sure looked like he had the Tar Heels on track for an easy win, with his putback with 2½ minutes left in the first half giving them a 49-24 lead.
But with Dixon and Thornton heating up, William & Mary outscored North Carolina 35-19 during the next 16½ minutes. Dixon hit three of his four 3s during that stretch - which also included the sequence that had the Smith Center buzzing.
After official Jamie Luckie reversed a block-charge call and gave the whistle to North Carolina's Brice Johnson with 11:14 remaining and the Tar Heels up 61-47, an incensed coach Roy Williams came onto the court while motioning for a timeout and was given a technical foul. Williams removed both his suit jacket and his glasses as a subdued crowd came to life for the first time all night.
William & Mary: The Tribe entered shooting 48 percent for the season but shot just 37.7 percent. They were just 7 of 27 from 3-point range after entering shooting 40 percent from behind the arc.
North Carolina: The Tar Heels have not lost to William & Mary since 1977 and have never lost to the Tribe in Chapel Hill.
North Carolina is at Clemson on Saturday.