By the turn of the year, punk had become a major media phenomenon in the UK. On 25 January 1977, the Clash signed to CBS Records for £100,000, a remarkable amount for a band that had played a total of about thirty gigs and almost none as a headliner. As Clash historian Marcus Gray describes, the "band members found themselves having to justify [the deal] to both the music press and to fans who picked up on the critics' muttered asides about the Clash having 'sold out' to the establishment." Mark Perry, founder of the leading London punk periodical, Sniffin' Glue, let loose with what he would later call his "big quote": "Punk died the day the Clash signed to CBS." As one band associate described it, the deal "was later used as a classic example of the kind of contract that no group should ever sign—the group had to pay for their own tours, recordings, remixes, artwork, expenses ..."
Mickey Foote, who worked as a technician at their concerts, was hired to produce the Clash's debut album, and Terry Chimes was drafted back for the recording. The band's first single, "White Riot", was released in March 1977 and reached number 34. The album, The Clash, came out the following month. Filled with fiery punk tracks, it also presaged the many eclectic turns the band would take with its cover of the reggae song "Police and Thieves". "[A]midst the Sex Pistols' inertia in the first half of 1977, the Clash found themselves as the flag-wavers of the punk rock consciousness", according to music journalist and former punk musician John Robb. Though the album charted well in the UK, climbing to number 12, CBS refused to give it a US release, believing that its raw, barely produced sound would make it unsalable in that market. A North American version of the album with a modified track listing was released in 1979, after the UK original became the best-selling import album of the year in the United States.
Chimes, whose career aspirations owed little to the punk ethos, had left the band again soon after the recording sessions. He later said, "The point was I wanted one kind of life and they wanted another and, like, why are we working together, if we want completely different things?" As a result, only Simonon, Jones and Strummer were featured on the album's cover, and Chimes was credited as "Tory Crimes". Strummer later described what followed: "We must have tried every drummer that then had a kit. I mean every drummer in London. I think we counted 205. And that's why we were lost until we found Topper Headon." Headon, who had played briefly with Jones's London SS, was nicknamed "Topper" by Simonon, who felt he resembled the Topper comic book character Mickey the Monkey. An excellent musician, Headon could also play piano, bass and guitar. The day after he signed up, he declared, "I really wanted to join the Clash. I want to give them even more energy than they've got—if that's possible"; interviewed over two decades later, he said his original plan was to stay briefly, gain a name for himself, and then move on to a better gig. In any event, Strummer later observed, "Finding someone who not only had the chops, but the strength and the stamina to do it was just the breakthrough for us".
In May, the band set out on the White Riot Tour, headlining a punk package that included the Buzzcocks, Subway Sect, the Slits and the Prefects. The day after a Newcastle gig, Strummer and Headon were arrested for stealing pillowcases from their hotel room. That same month, CBS released "Remote Control" as the debut LP's second single, defying the wishes of the band, who saw it as one of the album's weakest tracks. Headon's first recording with the band was the single "Complete Control", which addressed the band's anger at their record label's behaviour. It was co-produced by famed reggae artist Lee "Scratch" Perry, though Foote was summoned to "ground things" a bit and the result was pure punk rock. Released in September 1977—NME noted how CBS allowed the group to "bait their masters"—it rose to number 28 on the British chart and has gone on to be cited as one of punk's greatest singles. In February 1978, the band came out with the single "Clash City Rockers". June saw the release of "(White Man) In Hammersmith Palais", which surprised fans with its reggae rhythm and arrangement.
Before the Clash began recording their second album, CBS requested that they adopt a cleaner sound than its predecessor in order to reach American audiences. Sandy Pearlman, known for his work with Blue Öyster Cult, was hired to produce the record. Simonon later recalled, "[R]ecording that album was just the most boring situation ever. It was just so nitpicking, such a contrast to the first album ... it ruined any spontaneity." Strummer agreed that "it wasn't our easiest session." Although some listeners complained about its relatively mainstream production style, Give 'Em Enough Rope received largely positive reviews upon its November release. It hit number 2 in the UK, but it was not the American breakthrough CBS had hoped for, reaching only number 128 on the Billboard chart. The album's first UK single, the hard rocking "Tommy Gun", rose to number 19, the highest chart position for a Clash single to date. In support of the album, the band toured the UK supported by the Slits and the Innocents. The series of concerts—there were more than thirty, from Edinburgh to Portsmouth—was promoted as the Sort It Out Tour. The band subsequently undertook its first, largely successful tour of North America in February 1979.[60