"No Quarter" is a song by Led Zeppelin that appears on their 1973 album Houses of the Holy. It was written by John Paul Jones, Jimmy Page and Robert Plant. The song became a centerpiece at all Led Zeppelin concerts thereafter, until their final tour. It appears in both the film versions and both live album versions of The Song Remains the Same released in 1976 and expanded in 2007. It appeared once more in 1994 on Page and Plant's reunion album as the title track. It also appears on Led Zeppelin's 2012 live album Celebration Day, which documented their 2007 reunion performance at the O2 Arena in London. It was re-released in the deluxe edition of Houses of the Holy.

"No Quarter" was recorded in 1972 at Island Studios, London. It was engineered by Andy Johns and also mixed by Johns at Olympic Studios, London. The version that made it onto the album evolved out of a faster version Led Zeppelin had recorded earlier at Headley Grange, an old mansion in East Hampshire, England. Jimmy Page applied vari-speed to drop the whole song a semi-tone, in order to give it a thicker and more intense mood. In addition to the pitch change, the album version featured a very highly compressed guitar track, giving it a tone unique to Led Zeppelin. The effect is achievable today by means of running a dry signal through circuitry, at a much higher amplitude than the device is rated to handle. This phenomenon is commonly observed in Fostex and similar multi-channel recording equipment, dating back to the early 2000s. Likely a by-product of Page's compression, there are radar needles throughout the guitar track. Very little is known to the exact origin of the tone Page used, or how/why it was done. The guitar solo effect was achieved by direct injection and compression. The song features a brief Shepard scale at the close of the solo section at around the 4:45 mark. With his electric piano, John Paul Jones achieved a Fender Rhodes-like oscillator effect, as well as a real-time bass synth line, done on early Moog Taurus foot pedals in sequence with the keyboard track, which requires an amount of dexterity. Along with full-range intonation, the depression-sensitive bass pedals were then able to be modulated in-time with the riff, opening up the filter cut-off, rhythmically, judging by the amount the pedal is depressed. The result is a swampy, hollow, and deep bass sound, which was also compressed in the final cut.

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