Faldo won the last two holes of regulation with a birdie and a par and then agreed with Campbell that the sixth playoff hole would be their last one as darnkess fell over the Wentworth course.
The match will resume early Friday with the winner facing defending champion Ian Woosnam.
"We both decided that that was going to be the last hole," Campbell said. "I couldn't read my putt properly. I've never played a match as long as this, but it was fun. I just want to go and eat now, then have a couple of hours' sleep, then get up again."
The match was the longest of the 384 played in the 39-year history of the event. The previous record was 40 holes, achieved three times, including a loss by Faldo to Darren Clarke two years ago.
In other matches Thursday, Ireland's Padraig Harrington, who lost last year's final to Woosnam, beat Canadian Mike Weir, 4 & 3; Vijay Singh of Fuji topped Britain's Justin Rose, 1-up; and former champion Colin Montgomerie of Scotland edged American Fred Funk, 3 & 2.
Campbell missed a five-foot birdie putt at the 34th hole that would have won the match.
Faldo kept the match alive on the fourth extra hole with a birdie from 10 feet, after which Campbell sank an eight-footer to gain a halve.
"Well, that was an honest day's work at the office," Faldo said. "I am pleased I came back, obviously, but I need a breather now, thank you very much."
Montgomerie next takes on South African Ernie Els, the reigning British Open champion. The Scot has twice finished second to Els at the U.S. Open and was beaten in their only previous match play clash, the 1994 final.
"He is up in our matches, but I did beat him at Sun City (in the 1996 Million Dollar Challenge)," Montgomerie said. "That was my only playoff win and I just managed to get out of the country alive. I'm confident with what I am doing at the moment and hopefully he fears me as much as I fear him."
Ohio bar shooting arrested, charged with murder
McPhee, Cokas 'working on their marriage' after affair