He is now able to play for the Bees after a suspension for breaking Football Association betting rules which eventually amounted to 262 charges.
The Englishman has been out of action since Brentford's 1-0 defeat to Liverpool in May last year.
He has scored 32 goals in 64 Premier League games for Brentford.
Toney posted a meme via his X, formerly Twitter, account with the caption 'free!' on Wednesday afternoon, while his club also posted a welcome back message.
He is now expected to be involved in Thomas Frank's squad for Saturday's Premier League clash against Nottingham Forest.
"No doubt he (Toney) would like to come back, do fantastically well and give something back," Brentford boss Frank told the BBC after Tuesday's FA Cup third round replay defeat by Wolves.
"He missed playing football, missed being part of the team. It's a team he's really enjoying being part of, with some good mates, enjoying their football together, enjoying playing for Brentford and for the fans."
Before his ban, Toney had broken into Gareth Southgate's England plans and was seen by many as the first-choice back-up for captain Harry Kane.
Toney has also been the subject of intense transfer speculation since the summer, particularly from the likes of Arsenal, Chelsea and Tottenham.
However, the forward recently publicly stated he hoped to repay the faith and patience bestowed upon him by his club, which he has been at since signing from Peterborough in 2020.
"I have a lot to repay them and I can't wait to try and do that," Toney told Sky Sports last week when discussing the support the club had shown him during his time away.
"The club was right behind me from the first bit. The fans were behind me, which was a massive part," Toney added.
"Even when I wasn't at their games, they were singing my name. I got loads of messages on social media. A friend of mine sent me a video of the fans singing my name, I got goosebumps to know that they're still behind me, even though I'm not there.
"Everyone knows Brentford is a family club, they have been nothing but amazing for me. I can't thank them enough, especially the fans. They were behind me from the first minute as well. So it's kind of like I have a lot to repay."
Toney recently scored a hat-trick for Brentford's B team in a behind-closed-doors friendly against Southampton U23s.
