He was born in Kingsbury, a suburb of northwest London, in England, and was trained in the church choir as a young boy, beginning his musical career in the church's basement. In 1964, he was suspended from school for "having long hair", and given money to get a haircut. Instead he went home, used the money for other things, and never returned to school.
Squire was fond of experimenting with LSD in the 1960s, until an incident where he had a bad acid trip. He recalls that he spent months inside his girlfriend's apartment, afraid to leave, and it was during this time that he learned how to play bass. He recovered and never used LSD again.
Squire's early influences were diverse, ranging from church and choral music to the Merseybeat sounds of the early 1960's. Squire's first musical groups The Selfs, The Syn, and later, Mabel Greer's Toyshop, would introduce him to his early Yes collaborators Peter Banks and Jon Anderson and to Andrew Jackman.
During his first conversation with Anderson, the pair broke the ice by discussing one of their favourite groups, Simon & Garfunkel (Yes later covered "America") and Squire discovered that he and Anderson were both into vocal groups.
Yes released their first record in 1969, and though the band have had many personnel changes over the years, they have continued to record and tour for over 35 years. Squire is the only original member who has remained in the lineup throughout the band's tenure.
During the band's formative years Squire was frequently known for his tardiness, a habit that drummer Bill Bruford often complained about. Because of this, Squire would frequently drive at unsafe speeds to get to gigs on time, once causing a horrific accident on the way to a gig in West Germany after he fell asleep at the wheel, although miraculously nobody was injured.
As Squire, along with Alan White and Steve Howe, co-owned the "Yes" name at the time, the 1989 ABWH lineup without him (which contained Anderson, Bruford, Wakeman and Howe) could not record under that name.
Squire has concentrated overwhelmingly on Yes' music over the years, and his solo works have been few and far between. His first and only true solo record was 1975's Fish Out of Water, featuring Yes alumni Bill Bruford on drums and Patrick Moraz on keyboards and The Syn/The Selfs alumnus Andrew Jackman also on keyboards. Squire was later a member of the short-lived XYZ (eX-Yes/Zeppelin) in 1981, a group composed of Alan White (Yes) on drums and Jimmy Page (Led Zeppelin) on guitar. XYZ recorded several demo tracks at Squire's home studio in Virginia Waters, but never produced anything formal (ostensibly because vocalist Robert Plant, still mourning for John Bonham, failed to get interested). XYZ never officially released any material, though two of the demos provided the bases for two later Yes tracks, "Mind Drive" and "Can You Imagine?". Squire also played a role in bringing Trevor Rabin into the Cinema band project, which became the 90125 lineup. Later, Squire would join with Yes guitarist Billy Sherwood in a side project called Conspiracy. This band's self-titled debut album contained the nuclei of several songs that had appeared on Yes' recent albums. Conspiracy's second album, The Unknown, was released in 2003. In late 2004, Squire joined a reunion of The Syn, subsequently leaving the band in May 2006.
Squire's bass playing is noted for being aggressive, dynamic, and melodic. Squire's main instrument is a Rickenbacker bass (model RM1999, serial number DC127), which he has owned and played since 1965. The RM1999 was a budget, monophonic version of Rickebacker's 4001 stereo bass. This model was imported into the UK by Rose Morris Ltd (hence the RM prefix on the model number) and, according to Squire's official website, was only the fourth bass of its type to be imported into Britain from the United States. This instrument, with its warmth and distortion, is a significant part of Squire's unique sound. Squire obtains his distinctive tone using only the neck pickup of his bass. In fact, according to John Hall (Rickenbacker CEO), the treble pickup (bridge pickup) of Squire's RM1999 is completely disconnected from the bass's circuitry and has been for many years. Another major factor in Squire's sound is a technique known as 'bi-amping'. By splitting the signal from his bass into dual high and low frequency outputs and then sending the low frequency output to a conventional bass amplifier and the high-frequency output to a separate lead guitar amplifier, Squire produced a tonal 'sandwich' that added a growling, overdriven edge to the sound while retaining the Rickenbacker's powerful bass response. He also uses fresh strings for every show.
Squire (who is self-taught) was also one of the first rock bass players to successfully adapt electronic guitar effects such as tremolo, phasing and the wah-wah pedal to the instrument.
Squire's vocals are also key to Yes' music, providing important harmonisation with Jon Anderson's distinctive countertenor.
Chris Squire is commonly known by his nickname "Fish", and the name is associated with many of his works (including his solo record, and the solo piece the fish (Schindleria Praematurus) from the 1972 Yes record Fragile). The name has multiple possible origins. First, his astrological sign is Pisces, and he is apparently a believer in astrology. Second, in the early days of Yes career, he once accidentally flooded a hotel room in Oslo, Norway while taking a shower, and Bill Bruford gave him the nickname. He may also have acquired this nickname because of the alleged amount of time he spends in the bath tub. On the 2007 documentary "The Classic Artists Series 3: Yes", Bruford says that the nickname arose because Squire spent long periods in the bathroom while they shared a house together in Fulham. The nickname can also be interpreted such that the species of fish, the bass is homonymous to the musical instrument, the bass.