During the 1970s, Morris guitars (particularly the W-series) often used a six-digit serial number. These are commonly interpreted in two ways:

S-YYXXX or YY XXX

If it is a 5-digit number, the first digit often represents the year of the decade (e.g., 4xxxx means 1974), followed by a two-digit month and a two-digit production sequence. The Late 1970s to 1980s: Terada and lida Factory Systems

The period from the mid-1980s through the late 1990s is perhaps the most difficult to decode. Morris has officially stated that serial numbers from , citing the involvement of multiple OEM factories. During this era, Morris guitars were often produced under contract by various Japanese factories, and no single serial number convention was universally applied.

The most common serial format for 1970s and early 80s "W-series" (Martin style) and "F-series" (folk style) guitars is a six-digit number usually found on the internal neck block or the back of the headstock. YYXXXX

Because serial numbers can sometimes fade or be entirely missing, the design and color of the internal paper label are crucial visual anchors for dating your Morris guitar. Early 1970s: The Round or Oval Labels

On some models, the serial number can be found —the rounded joint where the neck meets the body. One owner of a Morris W601m reported finding the number “41567” on the neck heel.

These numbers are generally sequential production codes and do not contain direct date stamps. To date these, you must cross-reference the internal label color (often round, rectangular, or featuring a distinct wood-grain pattern) with historical catalogs.