The centre, who joined the club in 2008 from Sharks in South Africa, could also make another century this weekend as he looks to add to his 97 points scored for the Men in Black.
The 26-year-old, who has also played his way into England colours during his four-year spell, says making his 100th appearance will be a proud moment.
“It’s a great reward for being with the club for some time and I’m very proud of the achievement,” he said.
“Saracens is a club I’ve got a huge amount of passion and pride to play for so it will be an exciting time for me.”
Barritt hopes Saracens’ match against Edinburgh will be the start of a long Heineken Cup campaign after he experienced the disappointment of crashing out in the quarter-finals last year.
He said: “It’s something you take week by week but we are confident.
“Having got to the quarter-finals last year, we were bitterly disappointed to get knocked out at that stage so we definitely want to just take it game by game but we see ourselves as challengers to go all the way.
“The Heineken Cup is the pinnacle of club rugby in Europe so it’s something there’s been a good build-up to and we need to be on top of our game so it’s something everyone wants to play in.”
Edinburgh made it to the semi-finals last year but have struggled so far this season in the league, winning two out of their opening six and none of their last three.
Barritt though insists Saracens’ opponents will provide a tough test at Murrayfield.
“The wonderful thing about the Heineken Cup is you get to play against teams you don’t watch week in week out so it’s definitely a case of being adaptable on the field and reacting to what they’re doing.
“But you never leave any stones unturned and we’ve done some analysis on what they do so we’re well-prepared for this game and we’re expecting a really tough match.”
Kick-off tomorrow is at 1.35pm.