The midfielder, who scored 16 times for the Dons last season, has interest from England and abroad.
English Championship side Millwall had a bid of £2million rejected, while it has been reported Serie A new boys have made an offer of a similar amount, with Turkish giants Galatasaray also mentioned.
Ferguson, since moving to the club from Hamilton Academical, has evolved into a talisman for Aberdeen, playing nearly 170 games and is now a regular in the Scotland squad.
The player’s uncle, former Rangers and Scotland captain Barry Ferguson, believes now is the time for a move noting the Dons would be in line for a healthy profit with two years left to run on his contract.
"He's gone up to Aberdeen and played virtually every game,” he told Go Radio.
"He's done a very good job for Aberdeen but I think going forward, he's at a stage where he has played a number of games and broken into the Scotland squad, so for Lewis's development I think it's time for him to move on.
"I'm sure Aberdeen will get financially rewarded.
"If you strip everything back then now is the time for Lewis to go and try and showcase his football talents - either down south or abroad."
Due to Ferguson’s family connections, a move to Rangers has often been touted. However, his uncle was coy on the matter, expressing his hope that the midfielder reaches the highest level possible.
"I would love nothing more than for Lewis to go and play at the highest level," he said. "He's at a good level now and at a good club. I'm not being disrespectful.
"I'm just thinking selfishly in terms of Lewis' career. I do think he has another level or two to go up and I think now is the time for him to go and try to find the right club for him.
"He's played a lot of games and scored a right few goals for Aberdeen and he's an international so Aberdeen will want to be well compensated."