Arr started his Worcester Warriors story in the club's mini/junior ranks before gaining a place in the club's highly successful Academy system.
The 21-year-old went onto to make his senior debut in 2008 and this season has established himself in the first team, making 22 appearances to date and scoring tries against Olympus rugby XV Madrid in Spain and Gloucester at Kingsholm.
"I'm over the moon to have signed," said Arr. "It's great to agree to the new contract and continue my connection with the club. I have been here since a young lad so I can't imagine playing anywhere else.
"I've really enjoyed this season and getting a run of games in the first team. It's something that I haven't been able to do in previous years but this season I have got the shirt and I'm relishing every second of it.
"I have been fortunate to work with some great coaches at Warriors, they have made a big impact on my career and that is something I am keen to continue.
"Andrew Stanley and Gary Meechan, in the Academy, is where it all began for me with all the work they put me through. The first team coaches, with Billy McGinty and Matt Powell, are now working on my game and I really feel I am benefitting.
"It's great to sign the new contract at Warriors, but my focus remains on this season and getting my head down. There were a lot of positives from the Newcastle Falcons game and we need to use that in our next few Guinness Premiership games to kick on."
