The 34-year-old missed the entire campaign through injury as the Cherries earned a place in the Championship, but boss Eddie Howe still offered the former Southend keeper a new deal.
Flahavan suffered a shoulder injury during pre-season and, while he recovered enough to play in the Hampshire Senior Cup, was unable to force his way back into the first XI.
And he is full of gratitude to the club's manager for giving him another opportunity with the club next season.
He told the club's official website: "I applied myself like I always do in training and whatever game I've got to play I just do what I've done for 17 years.
"The way I apply myself is how I do it every day, and fortunately for me I was lucky enough that the manager saw that, so I am thoroughly delighted."
Flahavan feels the Cherries are well equipped to survive in the Championship following their promotion.
"It will be a jump which I think the lads will be able to handle definitely, but we are not going to have it all our own way next season like we did this year," he added.
"(The) quality is higher but I'm sure that with what we've got, and if there are going to be any additions during the summer, we'll have enough to definitely be able to compete.
"I think these lads are hungry and they want to do well and kick-on in their careers, so that goes a long way as well. Hopefully we can get off to a good start in that division and try and maintain that, and who knows where we'll go."