Yamaha Serial Number Decoder Guide
Our summary of the maker official system - not a replacement for it. Serials can be inconsistent, reused, or faked; for valuable instruments confirm with the maker.
Yamaha official FAQ and serial-system PDFs cover acoustic/classical and electric/bass systems separately, and you need the serial plus the Made-in country to work out the year. Important caveat from Yamaha: many systems repeat every 10 years, so a decode can give several possible years - narrow it down with model features. Older seven-digit acoustic serials (about 1967-1976) are sequential and cannot be dated exactly. Serial locations: acoustic label/neck block, electric headstock.