Also at the Friday noon service at the Church of St. Ignatius Loyola in Manhattan were Amy Adams, Mary-Kate Olsen, Olivier Sarkozy, Justin Theroux, Joaquin Phoenix, Ethan Hawke, Ellen Burstyn and Spike Lee.
People.com said 10 pallbearers carried the casket containing Hoffman's body into the church, as the Oscar-winning actor's longtime girlfriend, Mimi O'Donnell, and their three young children followed.
A private wake was held Thursday night at the Frank E. Campbell Funeral Home in Manhattan and a larger memorial service is being coordinated for this month, the magazine said.
The 46-year-old actor was found dead of a suspected heroin overdose Sunday.
His film credits include "Twister," "Boogie Nights," "The Talented Mr. Ripley," "Capote," "Doubt" and "The Master."