The script is currently being written. The actor hopes the idea will make it to the finish line.
The anthology began with 1989's Bill & Ted's Excellent Adventure, a movie about two time-traveling metalhead slackers. The pair's music is destined to become the basis of a future utopian society, but that can't happen unless they pass their high school history class and graduate.
Since then, the concept has been spun off into a comic book series, two TV shows, and two additional movies. The latest film, Bill & Ted Face the Music, came out in 2020 – nearly three decades after the first sequel was released in 1991.
"We're tinkering with a fourth movie idea that all of us like, and the guys are going to write, so we'll see," Winter said during an interview for the Sarah O'Connell Show transcribed by Screen Rant. "It takes us time to get these things going, and we never want to do them unless they're great."
The actor said the writers want to make sure the script is up to snuff.
"They feel the same way, it has to be right. We love [the Bill & Ted movies] because they're oddball, and they're not typical mainstream films," Winter said. "They've never been cash-grab movies; no one has gotten rich off the Bill & Ted series. We really do make them sincerely from a place of love and interest."
He added that fans should be excited about the concept, even though he couldn't disclose any details.
"There's a really good idea that the writers came up with for a fourth that's kind of obvious," Winter said. "I don't want to give it away – I can't give it away because I would be drawn and quartered – but it is a really great idea, kind of an obvious idea. It will get written, and we'll see if we can actually get it made. It may be a little while."
For a time, Bill & Ted was mostly remembered as one of the ventures that helped turn Reeves into a mainstream star. He went on to star in high-budget projects like Speed, The Matrix and the John Wick series.
Reeves also plays bass in a Los Angeles alternative rock band called Dogstar. The group has released three LPs, including last year's Somewhere Between the Power Lines and Palm Trees.
As the decades wore on, movie lovers and critics developed a deep nostalgia for Bill & Ted. They appreciated the way the film fused boneheaded teenage antics with science fiction, history and Greek philosophy.
Winter's acting career never took off like Reeves', but he did have roles in movies like Freaked, which he directed, and The Borrowers.
He's also directed films including Bar-B-Que Movie, Deep Web: The Untold Story of Bitcoin and the Silk Road and Downloaded. The 2012 documentary about Napster and the rise of file-sharing premiered at SXSW.