DATING YOUR FENDER
For most of Fender’s U.S. instrument production history, production dates have been applied to various components. Pre-1977 Fender guitars have a serial number stamped on the bridgeplate or neckplate, later models are usually printed on the headstock. If you have a guitar serial number that is before 2010 you can try the Guitar Dater Project link below otherwise read on.
From late 1965 to sometime in 1976 the neckplate had a Fender logo F as well as the serial number. Starting sometime in 1976 has the serial number on the headstock but on earlier models the number could be off as much as two years.
Most notably, production dates have been penciled or stamped on the butt end of the heel of the neck of most guitars and basses, although there were periods when this was not consistently done (1973 to 1981, for example) or simply omitted. Neck-dating can be useful in determining the approximate age of a guitar, but it is certainly not definitive because the neck date simply refers to the date that the individual component was produced, rather than the complete instrument.
Given the modular nature of Fender production techniques, an individual neck may have been produced in a given year, then stored for a period of time before being paired with a body to create a complete guitar, perhaps, for example, in the following year. Therefore, while helpful in determining a range of production dates, a neck date is obviously not a precisely definitive reference.
Most specifications for a given Fender instrument model change little (if at all) throughout the lifetime of the model. While there have been periods of dramatic change, such as the transition periods between the Leo Fender years and the CBS years or the transition between the CBS years and the current ownership most models are generally feature-specific and do not change from year to year up to 2009. Fender instruments built in the United States and Mexico changed not once but twice for 2010 and onward.
2010 onwards
First off serial numbers began with 10 and were stamped Made in USA (or Made in Mexico) then it changed to have a US or MX prefix before the number.