His publicist told ABC news: "He's happily reached his 100lb weight-loss goal. He went from 287lbs to 187lbs and is in the best shape of his life."
Tom previously admitted his 11-month-old son Jax Copeland, whom he shares with his wife Ashley Groussman, 37, had encouraged him to lose the weight after years of fertility problems.
He said earlier this year: "Something inside of me changed. I knew I needed to live as long as I could. The moment I saw [Jax] I realised he deserves the best."
The 'Sons of Anarchy' star also admitted that he used to be embarrassed by his body and would get upset when his clothes were too tight for him.
He explained: "There was a lot of shame. One time I had a tailor come over and sew the weights into my suits - this is what you wear when you are 210, 220, 240, 300. That saved me the time of going into my closet and getting so upset and frustrated."