1970 Timeless Anthem With One of Rock's Most Mysterious Titles Became the Band's Greatest Song
You know it when you hear it, but do you know what it's actually about? Chicago's landmark single "25 or 6 to 4" has been the source of many a conspiracy theory, from gambling predictions to code for psychedelics, but do some light digging, and you'll learn that the meaning behind this soaring brass-rock favorite is as mundane as telling time.
"'25 or 6 to 4′ is a song about writing a song," Chicago's trombonist, James Pankow, told Backstage With Joe Chambers in 2018, via American Songwriter. "Robert was laying on the floor of his house in the Hollywood Hills looking over the city of Los Angeles just before dawn. He had been up all night."
The "Robert" Pankow mentioned is, of course, Robert Lamm, keyboardist and singer for the band. And he indeed confirmed Pankow's explanation. The song's title refers to the wee hours of the morning, specifically 3:35 a.m. (25 minutes to 4) or 3:34 a.m. (26 minutes to 4), when Lamm was wrestling with writer's block.
"I was living with a bunch of hippies up above Sunset Strip," he said on The Chris Isaak Hour, via Songfacts. "One of the advantages of this particular house was that it was in the Hollywood Hills and I could look out over the city late at night. I wanted to try to describe the process of writing the song that I was writing. So, 'Waiting for the break of day / Searching for something to say / Flashing lights against the sky' - there was a neon sign across the city. That song came from the fact that it was 25 or 6 to 4 a.m. in the morning when I looked at my watch. I was looking for a line to finish the chorus."
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Chicago famously calls themselves the "rock and roll band with horns," with their distinct sound a blend of jazz, rock, brass, prog rock, and pop. Their oeuvre includes a broad mix of ballads, soft rock, R&B, and soulful Motown-inspired hits. So when Lamm said he brought the bones of a song to his band who then transformed it into a masterpiece, well, that's exactly what happened.
"There was definitely a lot of raw material," he said. "I thought it was a song when I wrote the words down, and I brought the charts to rehearsal, but it wasn't really a song until they all played it."
The result was an instant rock classic, with Lamm on the organ and verse vocals, Peter Cetera handling the soaring lead vocals and brass, Terry Kath manning the guitar and delivering a killer solo, as well as James Pankow on the trombone, Lee Loughnane on the trumpet, and Walter Parazaider on the sax and flute.
According to AS and Billboard, the symphonic jam became the band's signature closing track for live shows.
"Beyond the blaring brass was an unforgettable performance from Kath," Billboard said, "who unleashed crunching hard-rock hell on this tune, plus an urgent, high-flying vocal from Cetera. A full-band effort from one of the greatest big-band rock acts of any era."
Since its release as a single in June 1970, the anthem has become a pop culture staple, too, appearing in everything from movies, series, and commercials to video games. AS also noted that it's a popular choice for school bands.
Despite not hitting No. 1, the track became Chicago's first Hot 100Top 5 single (No. 4) and became the band's most enduring hit, with Billboard even naming the orchestral feat the band's best ever.
"There's a reason why Chicago has chosen ‘25 or 6 to 4' as its set closer for virtually every concert this century, including its dazzling Rock and Roll Hall of Fame induction in [2016]: It's the band's greatest song, a banner encapsulation of the rock, soul and horns sound that has brought the sprawling outfit immeasurable success over the last 50 years."
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This story was originally published June 3, 2026 at 11:25 PM.