Seiko Serial Numbers
Distribution of the data setCaseback data were stored in the format of pictures with calibre, case, subcase, factory code, YYMM and serial number contained in the file name. Data were imported and analyzed with MS Excel. Data source for the divers watches: eBay (approx. 85%) and various watch fora (approx. 15%).As of August12 2012, the archive contained a total of 1570 caseback pictures of divers watches, figures 1 and 2 show the distribution of the data set per movement (figure 1) and for movement/case/subcase combination (figure 2).
Absolute Production NumbersThis is the first time I try to publish some figures on the absolute production numbers of the series I study. At this stage, I can only present data on watches with the 6-digit serial numbering system, I have not yet found a way to interpret the 7-digit that makes sense to me. Furthermore, it must be clearly noted that the data in my archive are not yet at all sufficient to allow an accurate determination of absolute numbers. The data I will present are thus to be interpreted as ballpark numbers but in my opinion are (1) the best data available so far and (2) should give at least a good impression of which numbers we are dealing with beyond orders of magnitude.Data for 6-digit watches are thus are based on the following assumptions:. Each case/subcase combination has an own serial number (e. G., separate serial numbers for 6309-7040 vs.7049).
Serial numbers are reset once a month, first watch produced carries serial number YM0000. Each Factory code has an own serial number (if thus watches were produced in two different factories within the same month, both factories applied their own serial number). All cases were built into actual watchesFor the analysis of absolute production numbers, the dataset was thus evaluated for the maximum serial number per calibre/case/subcase/factory code/YM combination and all the maxima over the production timeframe were summed up. In case that a watch was produced in two different factories, the subsums for factory where then added up.Results are summarized in table 1 and figure 3.
Seiko Watch Serial Numbers Rating: 5,8/10 7732 votesAn 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. The first number represents the year and the second number (or letter) represents the month (1-9 for Jan.-Sept. And O,N and D for October, November and December).For example if the serial number was 864825 and you knew the watch was made sometime in the 1970's it would indicate it to be made in June 1978.So, you’ve just purchased a used or new Seiko watch. Have you ever wondered when your watch rolled off the assembly line at the factory?
In other words, when was it manufactured? Questions relating to the production date of Seikos frequently pop up in various watch forums from time to time.
Well, in case you didn’t know this, the answer to this question actually lies in the set of numbers that are etched or printed on every Seiko watch made.Chances are if you ask watch store assistants when that particular Seiko watch you’re interested in buying was made, you’ll get a blank expression from them. Either that, or they’ll come up with an excuse for not knowing by saying that it’s a new arrival (yeah, right!) 🙂 You can’t really blame them for not knowing because watch sellers are in the business of selling watches, period.
From my experience many Seiko dealers aren’t watch enthusiasts themselves.They’re more interested to get a sale from you rather than discuss the history or significance of that Seiko watch that you’re looking to purchase. Well, I’m a firm believer that knowledge is power.
And if you have that knowledge, you have an edge over the seller that could be very useful.Especially when it comes to bargaining for a better price for that new, old stock (NOS) Seiko that caught your fancy. File photo of a typical watch store in Kuala Lumpur.Chances are that the female store owner in the picture doesn’t even know when the Seiko watches in her shop were made, 🙂 If the store owner senses that you know more about that watch than he or she does, there’s a good chance that you can bargain for a more realistic price.
I have gotten a few discontinued Seikos in this manner, saying 'Hey look, this watch is eight years old!It can’t be worth the price you’re quoting me!' Fortunately for me, the watch dealers relented to my counter offers and I got them for the price that I wanted. They probably figured out it’s better to sell off the watch now than risk their capital tied up in old stock that nobody else is interested in. Let’s find out how to date your Seiko watch and I don’t mean socially!
😉 Where to look for the serial number To locate the serial number, you’ll need to flip over your watch and examine its caseback.Seikos with solid casebacks (plastic, stainless steel or titanium) will have the 6-digit serial number etched in a straight line. Those that come with glass display backs like modern Seiko 5’s have the numbers printed horizontally on the glass display back but the numbers are usually faint and difficult to read.Higher end Seikos with display backs, like the 6R15 caliber Premier or 7L22 Sportura for example, have the serial number engraved not on the glass but on of caseback’s rim. Here are three examples of Seiko casebacks depicting their serial numbers.Type I: Seiko 5 glass display back: Basic Seiko 5 models made from the year 2002 onwards have clear glass display backs as you can see above. The 6-digit serial number is always located at the opposite end of the 'SEIKO' text. The numbers are faintly stamped from the inside of the glass.You’ll have to tilt the caseback towards the light to read the numbers properly or better still, use a magnifying glass.
The Seiko 5 in this picture is from February 2004.Update: Some very recent model Seiko 5s have the serial number printed not on the glass but along the caseback rim. If you can’t see the serial number on the glass, then look for them on the caseback rim (usually located on at the bottom part of the caseback). I guess Seiko decided that it’s easier and cheaper to produce spare display backs without having to etch the serial number individually. Type II: Display backs on higher end models: In more expensive Seikos with glass display backs like the Premier 6R20 pictured above, the serial number is usually found engraved along the rim of the caseback.Unlike the rest of the identifying text, the serial number is printed in a straight line. Why doesn’t the serial number follow the curvature of the rim? I’m not sure but I think casebacks are manufactured en masse and the individual serial numbers are stamped on later prior to packing and shipping from the factory. Anyway, the Premier pictured above was made in August 2007.
Type III: Solid metal caseback The majority of Seiko watches come with solid metal casebacks (stainless steel, solid gold, gold plated or titanium) and the serial numbers are also stamped in a straight line. Pictured above is a the caseback of an SKX007K Seiko dive watch.Reading numbers off solid metal casebacks is pretty straightforward. The Seiko diver above is from November 2003.How to the serial number works Every Seiko watch manufactured is given a 6-digit serial number. There are however exceptions to this rule. Seiko watches made prior to the late 1960s, most probably 1967 have 7-digit serial numbers instead.Limited edition models with unique sequenced numbering, e.g.
123/300 (denoting the 123rd piece out of a total of 300 pieces) usually don’t have serial numbers. Limited edition Seikos are usually made within a very short time frame – perhaps not more than a few months in the year it was introduced. In this case you’ll need to know the intimate history of the model – for example, the 600m diver was released in 2000 with 1,000 pieces made.
You may not know the exact month the watch was made but suffice to say, the production year couldn’t be any later or earlier than 2000. To simplify things, I will use the 6-digit serial number convention. This table below describes the structure of the serial number.Digit Position Description Characters used Notes 1 Production year 0 to 9 Denotes the year in the decade, not absolute year 2 Production month 1 to 9, '0', 'N' and 'D' 1 to 9 denotes months of January to October. '0', 'N' and'D' denotes October, November and December respectively 3 Sequence number, thousands 0 to 9 The last four digits represent the running number of the watch 4 Sequence number, hundreds 0 to 9 5 Sequence number, tens 0 to 9 6 Sequence number, ones 0 to 9 Deciphering the serial number.
The remaining 4 digits represent the production number of the watch in a sequence. It is generally believed that the first watch produced every month begins with '0000' and the last watch made in that month ends with '9999'. Going by this convention, up to 10,000 watches of a particular model could be manufactured in one month.The sequence number is reset for the following month. Therefore if Seiko made up to 4,900 pieces in February, the last watch produced will have the the sequence number 4900.
For the following month of March, the first watch produced will have the sequence number 0000 instead of 4901. The following table below gives examples on how the serial numbers are interpreted: Caliber Serial Number Year Month Watch Number 7S26A 7 January 7872 7T32 8N1030 1998 November 1030 6105 2 October 421 6138 7 March 1999 6309 4D8001 1984 December 8001 8L35 2 May 9393 7S26B 7 June 23 Jayhawk’s Production Date Calculator Fortunately there is an automated method of determining when your Seiko was made. Savvy Seiko watch enthusiasts have been using to check when their watches were made. It’s linked from the Seiko & Citizen Forum and to my best knowledge, it is currently the only automated tool for dating your Seiko watch on the Internet. It’s easy to use – just enter your movement number and the serial number and hit the Calculate button.There you have it – your watch’s date returned to you in a matter of seconds!
🙂 However, there are a few caveats that you need to know when using the Production Date Calculator.Firstly, the results that are returned to you are based on the accuracy of the internal database table. There may be unintended mistakes in the range of the years entered into the table.
The calculator does not take into account for calibers that are made for more than 10 years. The production date calculator does not cover the entire list of Seiko calibers made. The problem lies in Seiko’s numbering convention as it used only one digit to represent the year.The first digit only signifies the year number in a certain decade (10 years). While it is true that Seiko movements are discontinued in less than a decade, there are however, some exceptions to the norm.A well known example is its very popular 7s26 automatic caliber. If you enter a serial number beginning with '7' or '8' for a post-2000 made 7s26, the date calculator will return you the years 1997 or 1998 respectively, which is off by a whopping 10 years! Even if you are certain that your watch was made in 2006, the date calculator will still think that it was made in 1996.Here’s why: The Production Date Calculator unfortunately doesn’t have the ability to account for calibers that have been made for a decade or longer. It merely checks the first digit in the serial number (the year of production) and compares it with its internal table of calibers with the starting year.
Since Seiko uses only one digit to denote the production year, the calculator cannot determine the exact decade the watch was manufactured. For instance, 7s26a caliber was first introduced in 1996 and therefore it naturally assumes that it was from the 1990s. The replacement 7s26b caliber however, came out in late 2006 but the production calculator does not take this into consideration. Caseback dating dilemma: Was this Seiko 5 Superior from January 1997 or January 2007?It’s actually from 1997.
Manually dating a Seiko watch Fortunately, there is an alternative to the Production Date Calculator if it returns you erroneous or dubious results. In order to do this, you will have to date the watch by manual means that can give you an approximation or the exact the decade the watch was made.
If you’re interested in pursuing this topic, learn how to manually date a Seiko watch. Hi Detlev, I’m not familiar with the Seiko 9020 quartz movement but designs based on this caliber suggest that it’s an 80s watch rather than the 1990s. Therefore it’s quite probable that yours was from June 1985. Although your serial number has the number 177, it is actually piece #178, because the first watch made in any month has the ending 4 digit numbers starting with “0000” and not “0001”.Unfortunately I have no idea how many pieces of your particular model were made. You’ll have to contact Seiko Japan to get the information. Hope this helps, Quartzimodo.Hi Clemualb, The reason that I asked for the serial number verification is because a 7-digit serial number applies to vintage Seiko watches made between 1966 and 1967. Most Bell-Matics I’ve seen in pictures (I own two myself) are from the early 1970s.
It’s quite rare to see one that’s made in the late 60s. So there you have it – October 1967.
You have one of the earliest Bell-Matic models, which is a rare occurrence. The “Water Proof” marking also confirms that your watch has to be from 1967 and not 1977, because it if were from 1977 (about the time the Bell-Matics were discontinued) it would have “Water Resistant” marked instead. John Nelson (John N) is a contact of mine and he used to run a site dedicated towards Seiko Bell-Matics; he would know about the subject more intimately.I bought a 4006-6040 from him two years ago as he was liquidating his collection. Cheers, Quartzimodo.Hi Foxbat, I haven’t been poking my nose in watch stores for a long time, but word has it from the Seiko collector communities is that the 7s26C version did appear sometime in 2011. Some believe that the 7s26C has a more pronounced, elevated pinion in the movement for better height clearance for the main time hands. If this is true, then it should solve cases of sticking second hand that tend to rest exactly where the minute hand lies when the main spring is nearly unwound. So far I noticed that one of my watches (7s26B caliber) has this problem.Thanks for reporting your watch production dates.
Since you have observed your SNK315K is from December 2011 and your SNKE53K from June 2011, this narrows down 7s26C’s debut between the months between June and December 2011. More feedback from owners having the newer 7s26C movement are needed to pinpoint the exact month Seiko introduced the 7s26C. The new Seiko solar powered watches should be at least equal to Citizen’s Eco Drives.Actually Seiko has had solar powered watches dating to the late 90s or early 2000s, but they weren’t as popular as Citizen Eco Drive watches. For Seiko, they were busy pushing their Kinetic technology while Citizen had no choice but move forward with what they’re already good at – light powered watches.Once upon a time, Citizen made a few models based on its Eco Drive Duo technology (solar and kinetic movement charged), but they were quite expensive. Those watches were probably more efficient at charging using sources of light than the wrist movement, therefore it made the “kinetic” charging method redundant. I might buy one of those nice Seiko Solar chronographs this year. I saw quite a few models when I visited Singapore last October and was tempted to buy one, but I’ll wait for newer solar powered chronographs to appear.
Cheers, Quartzimodo. Thanks again Quartzimodo The reason I asked about Seiko solar was I saw a SNE031 advertised recently and considered buying it. I was waiting for the SNK315 to arrive and discovered that the two watches are virtually identical (37mm across and 10-11mm thick with very similar plain white/cream faces).In the end they were too similar, despite the different mechanisms, so I’ve changed tack (see your chronograph blog). Incidentally, as I once said before, I have a “venerable” 5M62-0AK0, s/n 386455, which I bought in Canberra on 9 February 2005 (18 months old at the time). None of the documentation tells me what the model (S.etc) is. Is there some way I can find out?
Hi Foxbat, I Googled for your Kinetic watch and found the reference number. It’s either the (white dial) or the (black dial).The SNE-series solar watches are one of Seiko’s latest revivals into the solar powered watch scene and this time they’re putting more effort into promoting them. I expect them to be vastly improved versions of their earlier efforts. Its solar panels are located behind the translucent dial like the surface of a white ping pong ball. Your Promaster AV0031-59A’s solar panels on the other hand, are located at the subdial apertures.
It’s best that you view the SNE031 yourself before buying it, in case you prefer solid, opaque dials. Cheers, Quartzimodo.Thanks again. You are a champion!My SKA is the black 198P. There is considerable similarity to my recently bought SMY115 – which you gave the suffix P, which I assume means that both watches were assembled in Singapore.Does the suffix K indicate Hong Kong assembly? I shan’t be buying the SNE031. I was looking at it amongst a group of watches but in the end I plumped for a Citizen CA0021-53A, which had features that encapsulated the whole group.Your education, and that of one or two others, has shown me the absolute need to shop around for watches, especially via mail order.
Hi Foxbat, Yes, the “K” suffix designates a Seiko watch that is cased in Hong Kong (China). Do note that some models that are exclusive to the U.S.Market do not have any letter suffix at all.
Seiko Serial Numbers 381332
Some examples include the SKXA35 and SNM035 automatic diver’s models. They are not referred to as the “SKXA35K” or “SNM035K”. Market models also have the country of manufacture printed on the dial to comply with the American Federal Trade Commission labeling laws. For watches that are made in China, they are clearly marked “Mov’t Singapore” or “Mov’t Malaysia” and “Cased in China” in fine print on the dial. The Citizen CA0021-53A is a great looking watch, but personally I avoid watches with no contrast between the dial and the hands/markers.They’re hard to read the time in dim lighting.
BTW, have you ever considered Orient automatic watches before? I have an Orient and it’s a very fine dress/sports automatic, with a power reserve indicator and perpetual world time. For its asking price, Seiko offers nothing like it. A unique feature of the Orient CEY04002B is its sapphire glass display back, which is quite unusual as most watches with see-thru casebacks use the cheaper mineral glass. This watch is equally eye-catching as the Citizen Promaster E210 series and I’ve often received compliments whenever I wear it.🙂 cheers, Quartzimodo.
Hi again Three things: I looked at the SNK315K I received allegedly from the US this week but the curiosity is it does have the suffix K and no origin printing on the face, even with a maginfying glass. Perhaps a US entrepreneur imports for export but not for the US market? In that regard, I used the hotlink re the Orient CEY04002B and came up with an LA supplier who clearly indicated “USA only”.
I subsequently looked at a Singapore supplier just out of interest as my budget and brain are exhausted for the time being.I will probably end up with a simpler Orient power save indicator automatic some time in the future. I take your point about the CA’s white on white but we all wear watches by circumstances and mood. I go to meetings regularly and generally wear black faced watches like my Citizen BM8430 or my SKA (thanks again for identifying it) or SMY Seiko kinetics which allow me to glance at the time. I have drawn up for fun and some self-indulgent justification a list of my 18 “active” watches and how I intend to use each of them.
But now this 66yo “semi-WIS” is going to withdraw from the field for a while. All the best, thanks a million and cheers. Hi Foxbat, In the early 2000s, Asian market Seikos were available exclusively from Southeast Asian and Hong Kong based sellers.Things have changed since then, with a few enterprising Far East based watch sellers setting up offices in the U.S. To cater for the North American market. Such watches, including your SNK315K Seiko 5 are considered parallel imports from Seiko USA’s point of view.
The Orient CEY04002B is a watch that’s worth saving for, because it’s a lot of watch for the asking price. There is also a Japan market, limited edition model that uses the identical movement but sells for USD2,000.
I’ve seen the watch in person and have taken photos of it at my regular watch store. After a year sitting on the shelf, the watch was returned to the distributor as nobody wanted to spend that much on a “mere Orient” watch.If I could offer some advice, it’s better to save up towards something that’s more unique rather than going for quantity for your collection!
Take it from someone who’s owned a little over 80 timepieces. 🙂 Quartzimodo.Oh dear, Oscar Wilde is winning! After your last advice I internetted Orient automatics and you are of course right, they are a great idea. The reviews from far and wide are universally, or almost, glowing.I have ordered a FEU07008DX as a starter, just over $100 delivered and very interesting looking.
As to the CEY04002B, what about the slightly more expensive CFA05001B?I prefer the look of the latter and the specs seem very similar. My only problem with having a surfeit of automatics is keeping them all going. I know you say it’s not really necessary but an Orient site suggests they should be wound at least once a week to keep the lubrication constant. It’s also suggested that it is best practice to keep an automatic on your wrist for eight to 12hours a day.
Obviously with a reasonable number of watches, including potentially five automatics, that won’t happen. As usual, I look forward to your invaluable advice.Hi Quatzimodo I got the FEU and to my surprise and mild disappointment it turned out to be a FEU07005BX instead of the 8D; the former is thicker, heavier and mineral rather than sapphire. One pleasant surprise is it features a Breitling Navitimer, or copy.
Seiko Serial Number 810568
The manual doesn’t explain it but googling naut and stat did. I took you advice, sort of, but went for the CEY04003W0, as you might have foreseen. Unlike you I do like the white on white look; my Citizen CA0021-53A is a particular treasure. Thank you for all your expertise, advice and interest. After $2000 or so I’ve done my dash and reached a respectable 20 watches so it really is time to stop!Hi Michael, Congratulations on buying both (wow!) Orient watches.
🙂 The model FEU07005BX is most probably a recent model as I haven’t been following developments of watches for some time. The scale that’s printed on the edge of the dial is an E6B Flight analog computer which works on the slide rule principle. On watches today, the E6B scale is mostly for aesthetic/decorative purposes as even single engined Cessna/Piper pilots use digital flight computers for navigation. I have several watches with the E6B scale on them and never bothered to learn how to use it, lol. Your purchase of the white dialed CEY04003W0 didn’t come as a surprise to me (I was nevertheless elated that you chose this model) as from your past comments, you like white-on-white watches.
I have only three or four white dialed Seiko models, but their index markers are black, providing some contrast.It’s a good thing that you selected the CEY0400 series, because the small perpetual second hand departs from the traditional long sweep second hand on your other timepieces. Due to its short hand, the individual ticking motion is not discernible to the eye and this gives it a fluid-like motion like the second hand of a Seiko “Quiet Sweep” wall clock or a Seiko Spring Drive watch. My advice is not to buy too many watches within a short span of time, unless they are on the endangered species list (read: vintage/discontinued). Spacing out your watch purchases will give you time (pun not intended) to enjoy your most recent purchase. The CFA05001B is a newer model to the CEY0400 series; it sports a different caliber than the latter. Modern mechanical watches don’t really need to be worn all the time – there are millions of unsold automatics sitting in retail stores all over the world that haven’t been “shaken” in six months or longer, but they still work nicely.
You don’t need to buy an automatic watch winder unless you own some exotic Swiss mechanical with complications like a perpetual calendar.Such watches can have complex setting procedures, that’s why their owners invest in watch winders to avoid the hassle of setting these watches. Enjoy your new watches in good health! 🙂 Quartzimodo. Hi Rick, You have one of the more collectible Seiko quartz diver’s watches. The 7548-700x series are generally well liked by most Seiko dive watch collectors and a Pepsi-bezeled 7548-700F can fetch between USD200 to USD250 depending on the condition and originality. The 7548-700x is commonly believed to have influenced the styling of the SKX007/SKX009 series, automatic divers which appeared in the mid 90s.Your watch was fully made in Japan by Seiko’s Suwa factory on March 1985. The five jeweled, 7548 movement is robust and long lived.
It requires an Energizer 301 or Seiko/Maxell SR43SW 1.55 silver oxide battery, with a 3-year lifespan. Thanks for the compliments! 🙂 Quartzimodo.Hi Quarzimodo Thank you for your encouragement and advice.
I agree I have dived in rather precipitately. Fortunately I have decided to stop at 20 with the two Orients. I had expected to stop at 18 but your salesmanship for the Orients was so excellent that I had to expand my collection accordingly.
My philosophy is not to have a conventional collection of collectable watches but to be able to have a cross-section of horological ideas and to wear them all at different times, with the possible exception of the Seiko 6139-8002 (still being repaired) and the Citizen 49-9714, both of which have sentimental, rather than practical, value.