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Classic watches and those that are well-maintained can become collectors' items. An important element of investing in a watch like those made by the Seiko company is knowing and identifying the design watch you carry. Watches that are no longer in production are more in demand by collectors. Newer watches boast advanced features and sleek designs. Deciphering the Seiko serial number and understanding the bits and pieces that make it up takes a little detective work on your part. Break out the magnifying glass and note paper.

Wipe clean the face and back of your watch with a soft, non-abrasive cloth. Turn over the watch face-down on a soft, cloth-covered surface to prevent scratching the watch face and dial.

Using your magnifying glass, look carefully on the back plate and around the edges of the back cover for numbers and letters. Write down the series of numbers and letters you find engraved on the back of the watch.

First numbers, from 1 to 9, represent the year of a decade in which the watch was made. Letters represent the months of October, November and December. Each decade is represented in 10-year spans using this format. The beginning of a new decade can present a problem because certain numbers overlap.

The next character should represent the month, and can be a number or letter. Two sets of four-digit numbers with a dash between them represent the case and caliber numbers and can help you narrow down which decade you are working with.

The first four digits represent the movement. You can sort the designs of Seiko watches and narrow them further using the movement number and the various serial number portions.

The last four digits represent the model number you are looking for. Write out the entire serial number and the breakdown of its components for future reference and add it to your collection.


There are many designs and styles of Seiko wrist watches. Browse the company's online site to help you narrow down possibilities on the design year if you are unsure of the numbers used in your serial number.


Models are often discontinued after a period of time. To ensure correct appraisal of your watch's value, refer to a certified appraiser or jewler after you have identified to the best of your own ability, the model number and maker details.