The move is a change to the normal protocol of selecting a single individual and team officials had to gain permission from the International Paralympic Committee to make the move.
“We have witnessed some outstanding performances, and most notably from Sarah Storey and David Weir,” said chef de mission Craig Hunter.
“I'm thrilled and delighted that the IPC has recognised and agreed to our request to allow joint flagbearers at the closing ceremony.
“These athletes represent the spirit of Paralympic athleticism.”
Wheelchair racer Weir has been the star of the Olympic Stadium over the last ten days, with victories over 5000m, 1500m and 800m and won Great Britain's last gold of the Games in the marathon.
At the end of his fourth Games, the 33-year old Londoner now has a career haul of six gold, two silver and two bronze medals.
"It will be a great honour to come out to the closing ceremony carrying that flag,” said Weir. “I'm a proud Brit and Sarah is as well. She has done fantastically well too.
“To do it as a Londoner in front of a London crowd makes it even more special.
“The Games has been special for everyone; every Paralympian has said it’s been special. So to go out in the stadium will be a tearjerker. Not much is going to top this.”
Storey starred in the velodrome and on the road, winning the four golds to become Great Britain's most decorated female Paralympian, moving ahead of fellow 11-time gold medallist Tanni Grey-Thompson.
“I’m amazed at the news, I never expected it,” said Storey. “I’ve not been to a Paralympic ceremony since Athens and can’t wait to see the stadium. It’s a huge honour and it should be a very exciting night.”