Sam is not the name Ed Sheeran has given one of his guitars. Sheeran has named several of his much-used guitars, including Cyril, Felix, Lloyd and Trevor, making Sam the odd one out.
The names belong to Sheeran’s small-bodied acoustic guitars, many of which were built by Martin. His early mini guitars became closely associated with his stripped-back performance style, especially when he used a loop pedal to build complete songs live. Cyril, in particular, was an early and recognisable guitar covered with stickers and later inspired signature models.
The question can be confusing because Sheeran has owned and used many guitars over the course of his career, and different articles list older instruments, touring replacements or signature editions. The names are therefore not a complete inventory of every guitar he has played. Felix, Cyril and Lloyd are all documented names, while Sam is not among the commonly cited examples.
A related fact fans often ask about is why Sheeran uses small guitars: their compact bodies suit his playing style, portability and preference for a focused acoustic sound.