Dating Zippo Lighters
Since 1955, most Zippo lighters have carried a date code stamped on the base. Originally this was intended as a quality control record, so that lighters returned for repair could be identified as to when they were manufactured and if, for example, a number of lighters were returned with the same fault then Zippo could identify a possible defect in the manufacturing process or even a supplier of one of the components.
Even prior to the coding system we can go some way to identifying the approximate year of manufacture, as the stamping on the bottom has changed slightly over the years.
Lighters assembled at the Canadian factory are covered here - Dating Canadian Lighters
As lighters are meant to be used, coins or keys carried in the same pocket can cause scratches on the bottom of the lighter so it is necessary to look very carefully at the bottom, as the marking can be quite difficult to make out. A magnifying glass can be quite useful.
The first lighters (1933 to 1935) can easily be identified by the words "PAT PENDING MADE IN U.S.A." on the bottom. From 1936 until 1953 the bottom will have "PAT2032695 MADE IN U.S.A." Lighters made in 1953-1955 will have PAT 2517191 ® PAT. PEND.
PAT 2032695 Lighters (1933 - 1953)
PAT 2517191 ® PAT. PEND.
On the image below we can clearly see that there are four dots, either side of the word Zippo. The dots were used between late 1955 and 1965. with one dot being removed each year. As there were some alterations to the positioning of the text on the bottom line, some codes were used twice, therefore close attention should be paid to the text on the bottom line for lighters with 7 or 8 dots.
1955-1965 Dating guide
The next set of codes used upright lines either side of the word Zippo. These were used between 1966 and 1973. Again 8 lines were used for the first year of the series, with one line being removed each year.
1966-1973 Dating guide
From 1974 until 1981 the solidus (now commonly referred to as a forward slash) was used. In 1979 an error was made and the slash was removed from the left instead of the right
1974-1981 Dating guide
1982 saw the use of the reverse solidus (or backslash) and this continued in use until mid 1986.
1982-1986 Dating guide
In July 1986 the line symbols were discontinued and the lighters were then identified by a series of roman numerals. These were placed to the left of the word Zippo, which left the space to the right free. It was decided to print a letter to indicate the actual month of manufacture with A = January, B = February etc. The 1937 replica series introduced in in 1985 were the first lighters to carry the Roman Numerals and 1985 lighters are stamped with I, but no date letter. Early 1986 lighters of this series do have earlier date codes. This series continued until 2000
1986-2000 Dating guide
In March 2000 the roman numerals were supplemented with the actual year of manufacture (2000) printed below the roman numeral (XVI). Then in 2001 the roman numerals were removed completely and just the last two digits of the year were shown (01, 02 etc)
2000-2006 Dating guide