In 1974, Pat Mills and John Wagner headhunted Carlos from D.C.Thomson to work on IPC's new title Battle Picture Weekly, for which he drew Rat Pack and a lengthy run on Major Eazy (almost 100 episodes over the next two and a half years).
In 1977, he was asked to design a new character, Judge Dredd, for the new title 2000 AD, but when the character's first published appearance was drawn by another artist, Carlos refused to touch the character again for some time (since then though, he has come to be regarded by many as the definitive Dredd artist).
He returned to Battle, and then co-created the character Strontium Dog for IPC's new SF weekly, Starlord (though the strip soon moved over to 2000 AD). Ezquerra was almost the only artist to draw Strontium Dog until 1988, when the decision was made to kill off lead character Johnny Alpha in the story The Final Solution. Ezquerra disagreed strongly with this decision and refused to draw the story (though he would later return to the strip when the decision was reversed and Alpha was first revived in a series of flashback stories and ultimately raised from the dead).
He also drew Fiends of the Eastern Front; Rick Random; Tharg; Janus: Psi-Division; ABC Warriors; Anderson, Psi-Division; Durham Red; Purgatory and the Stainless Steel Rat for 2000 AD, as well as Third World War for Crisis and Al's Baby and Cursed Earth Koburn for the Judge Dredd Megazine.
Additionally, he has worked on occasion for American publishers including DC Comics (on Adventures in the Rifle Brigade; Bloody Mary; Hitman; Preacher; The Magnificent Kevin and War Stories, all with writer Garth Ennis, and Bob the Galactic Bum with Alan Grant and John Wagner), Black Bull (on Just a Pilgrim, also by Ennis) and Dynamite Entertainment (on Battlefields, also with Ennis).
Carlos occasionally uses the pen name L. John Silver, and now lives in Andorra. His son Hector Ezquerra now regularly inks his pencils.
In 2015 Ezquerra was awarded the San Diego Comic Con Inkpot Award for Achievement in Comic Arts.