The S540 is an S series solid body electric guitar model introduced by Ibanez in 1993. It is carried over from the US-only
1992 540S and replaces the earlier 540S model.
Notable new features of the S540 include the maple (rather than rosewood) fingerboard with a new style of inlays, an All Access Neck Joint and the HSH pickup configuration. Other features include a mahogany body, a maple Wizard neck and the Lo-Pro Edge tremolo with a locking nut.
The original 540S was offered in 1992 alongside two variants with names which adhere to the modern "series name + model number" format, the S540FM (with flamed maple top) and S540BM (with burl mahogany top). The new naming convention was adopted in late 1992 for the complete S series line including the S540. Even so the old naming style continued on through 1994 for the related Radius series model, the 540R.