Bill Lewis was a Canadian luthier based in Vancouver, British Columbia, whose shop at 3645 West Broadway became a gathering point for guitarists in the 1960s and 1970s. Originally a classical and flamenco player who had studied in Spain, including master classes with Andrés Segovia, Lewis built a small number of highly regarded electric guitars by hand, typically featuring a mahogany body, a 24-fret neck with computer-calculated fret spacing, and two custom-designed pickups.

The Bill Lewis Custom is most closely associated with David Gilmour of Pink Floyd, who used his 1970 Lewis for the main guitar solo on "Echoes" and in other Pink Floyd sessions of that era. Eric Clapton famously played a Lewis for an entire Blind Faith concert in Vancouver on August 9, 1969, and Jimmy Page is also among the players linked to the brand. Because the instruments were made in small numbers by a single builder, surviving examples are rare and turn up primarily through specialty dealers and the vintage market.

By the early 1980s Lewis had shifted away from guitar building and sold the lutherie side of the business to a group in California, where it was reorganized as Luthiers Mercantile, a supplier of tools and materials to other builders. Bill Lewis died in 1996.

Bill Lewis has 1 product cataloged on Equipboard, including Solid Body Electric Guitars. Their gear is featured by 4 artists, with the strongest followings in Rock. Notable users include David Gilmour, Eric Clapton, and Poison Ivy.