When is the serial number engraved to case?

[mjolnir2thor]

Hello fellow watch geeks!

I spent some time on the forum's search function this morning and was unable to locate information pertaining to when Rolex applied the serial number on pre-1970 cases. Does anyone know at what point the serial number (and model number) is applied to the case during the the manufacturing process?

I've read online that the case may be manufactured during a specific quarter (e.g., II 67) and due to the manufacturing process, parts turn over (1963: 1530 switch over to 1520 movement), supply chain delays, etc. watch completion may be months later. I thought I read that it took a full year to make a timepiece which may vary depending on the complexity of the watch.

Article Reference: A Note About Dating - Hodinkee (scroll down about to the middle of the article)

https://www.hodinkee.com/articles/ro...ference-points

Given my manufacturing experience, I would think the application of the serial number and model would be engraved on the case just prior of installing the movement. The engraving would not be performed unless the movement's assembly and testing completes/passes as to not waste the case. What do you guys think?

Any information my fellow watch enthusiasts provide would be appreciated!

[swish77]

I don’t know the answer, but why does it matter?

[mjolnir2thor]

Originally Posted by swish77

I don’t know the answer, but why does it matter?

Here’s the thing… let’s say I have a rare example of a timepiece made III 66 with a gilt dial but the serial number puts it in the range (although I’ve seen different versions of the serial number range) for the following year 1967. I would assume it take ~9 months to make and test the timepiece.

So in this example, we have a 1966 case (date on inside case back), 1966 open gilt gloss dial, and 1967 bracelet. So is it a 1966 or is a 1967? Maybe the way to express it as a circa 1966.

Thanks for asking.

[Tools]

Dating is an enthusiast construct, not a Rolex thing.

I'm think that cases are not engraved with a serial until needed. I believe that the serial number allocation is administrative, for example block xxx through xxx is allocated to Subs, the next block GMT, next DJ, and so on.

They don't make all of them at the same time, that would be impossible, so one block is made one month, another the next month, etc, then when they make a full run of all the models, they start all over again, perhaps only then finishing the batch of allotted numbers......... or it could take a couple of years to finish the allotted numbers.

Number allocations may take 2 or 3 years to complete using the 1 Million number as each full allocation throughout the line.

Serial numbers have nothing to do with "model year", and all of the dating charts are completely enthusiast generated, not Rolex published.

[Dan S]

I agree with Aaron, I can't see why it matters. The only issue would be whether the watch as a whole is plausibly original. If there is a massive inconsistency between the various parts, then people will always be skeptical, even though there can obviously be outliers. But that is based on a large number of observations of which parts are generally found with which other parts, not any particular year or date.

[mjolnir2thor]

Originally Posted by Tools

Dating is an enthusiast construct, not a Rolex thing.

I'm think that cases are not engraved with a serial until needed. I believe that the serial number allocation is administrative, for example block xxx through xxx is allocated to Subs, the next block GMT, next DJ, and so on.

They don't make all of them at the same time, that would be impossible, so one block is made one month, another the next month, etc, then when they make a full run of all the models, they start all over again, perhaps only then finishing the batch of allotted numbers......... or it could take a couple of years to finish the allotted numbers.

Number allocations may take 2 or 3 years to complete using the 1 Million number as each full allocation throughout the line.

Serial numbers have nothing to do with "model year", and all of the dating charts are completely enthusiast generated, not Rolex published.

Thank you for the response. It makes good sense to me!

I was unaware that these lists are not official from Rolex but from 3rd parties. Probably collected and then compiled into the tables I am finding on the Internet. That explains a lot! Appreciate it!

[mjolnir2thor]

Originally Posted by Dan S

I agree with Aaron, I can't see why it matters. The only issue would be whether the watch as a whole is plausibly original. If there is a massive inconsistency between the various parts, then people will always be skeptical, even though there can obviously be outliers. But that is based on a large number of observations of which parts are generally found with which other parts, not any particular year or date.

I’m using the serial number as a key point in determining the age of the watch; however, as I just learned those lists are not official (from Rolex) but should be used to get a general idea of the year of the timepiece. Totally agree with you in terms the consistency of parts also being a key factor.

In my example, a 1966 Gloss Gilt Dial with open chapter ring with a 1967 serial number is something to note, but the dial, movement model, etc. should give you an overall indication on the authenticity of the watch.

Thank you contributing!

[Dan S]

Originally Posted by mjolnir2thor

I’m using the serial number as a key point in determining the age of the watch; however, as I just learned those lists are not official (from Rolex) but should be used to get a general idea of the year of the timepiece. Totally agree with you in terms the consistency of parts also being a key factor.

In my example, a 1966 Gloss Gilt Dial with open chapter ring with a 1967 serial number is something to note, but the dial, movement model, etc. should give you an overall indication on the authenticity of the watch.

Thank you contributing!

I still think there may be a fundamental misunderstanding. As noted above, there is simply no such thing as a "1967 serial number". That phrase has no meaning.

[brandrea]

Originally Posted by Dan S

I still think there may be a fundamental misunderstanding. As noted above, there is simply no such thing as a "1967 serial number". That phrase has no meaning.

Exactly.

I bought a meters first 1.7m serial here on the forum years ago, as a birth watch. Problem is, depending who I asked it was a 66 or a 67

[mjolnir2thor]

Originally Posted by Dan S

I still think there may be a fundamental misunderstanding. As noted above, there is simply no such thing as a "1967 serial number". That phrase has no meaning.

Hmmm… if I understand correctly, the range the serial number falls into per the compiled chart only gives a general idea of the age (i.e., year). Yes?

[mjolnir2thor]

Originally Posted by brandrea

Exactly.

I bought a meters first 1.7m serial here on the forum years ago, as a birth watch. Problem is, depending who I asked it was a 66 or a 67

Your post is exactly why I posted this thread. Now I get it.

[TuRo]

Broadly speaking official certified Rolex watch calibres of the 50s, 60s and early 70s took a while to get returned from BUREAUX OFFICES de Controle de la Marche Des Montres and reunited with the rest of the watch. The COSC institute set up in 1973 streamlined the process a lot .

From a dating point of view caseback were numbered up to 1974 - when it was dropped unfortunately - and case-back-numbering many argue, is more accurate than serial number dating....although even these were picked out of factory model 'stock bins' so can be a QTR or so out of kilter.

Therefore, it's not uncommon to see say an early c.o.s.c 1675 take 2 or even 3 years to get to a dealer and then on display to prospective buyers - with later pieces this period post-73 institute set up make that delay become less and less.

[Tools]

Originally Posted by mjolnir2thor

Hmmm… if I understand correctly, the range the serial number falls into per the compiled chart only gives a general idea of the age (i.e., year). Yes?

This is correct.

We should use the charts to note obvious outliers, rather than absolutes. We also should note that 44xxxx and 47xxxx, and likely others, are known blocks for replacement cases. Rolex does not go back to pluck an era specific serial allotment number

[Dan S]

Originally Posted by mjolnir2thor

Your post is exactly why I posted this thread. Now I get it.

If you want to refer to the case, just use the serial, mentioning a year is pointless. So you could ask something like "is a 1,754,XXX case serial consistent with a II-66 case-back, and a gilt-gloss dial?"

[mjolnir2thor]

Originally Posted by Dan S

If you want to refer to the case, just use the serial, mentioning a year is pointless. So you could ask something like "is a 1,754,XXX case serial consistent with a II-66 case-back, and a gilt-gloss dial?"

Great... got it. Thank you (and others) for putting me on the right road.

[Filipão]

Once upon a time...

Before all the hype, "they" did supply all info requested, so on some of my watches I know the (almost) precise date of production.

[Dan S]

Originally Posted by Filipão

Once upon a time...

Before all the hype, "they" did supply all info requested, so on some of my watches I know the (almost) precise date of production.

That is so cool, I remember when you showed some of this before.

[mjolnir2thor]

Originally Posted by Filipão

Once upon a time...

Before all the hype, "they" did supply all info requested, so on some of my watches I know the (almost) precise date of production.

I didn't know that this service was provided in the past... learning something new in this thread yet again! Sadly the key word in your response is did , I assume Rolex no longer provides this service.

It would be great if Rolex converted their hard copy records into electronic format and have the records searchable in a database by serial number. Perhaps there are legal ramifications... anyway one can dream!

[springer]

Originally Posted by TuRo

Broadly speaking official certified Rolex watch calibres of the 50s, 60s and early 70s took a while to get returned from BUREAUX OFFICES de Controle de la Marche Des Montres and reunited with the rest of the watch. The COSC institute set up in 1973 streamlined the process a lot .

From a dating point of view caseback were numbered up to 1974 - when it was dropped unfortunately - and case-back-numbering many argue, is more accurate than serial number dating....although even these were picked out of factory model 'stock bins' so can be a QTR or so out of kilter.

Therefore, it's not uncommon to see say an early c.o.s.c 1675 take 2 or even 3 years to get to a dealer and then on display to prospective buyers - with later pieces this period post-73 institute set up make that delay become less and less.

There is a mistake in this post!!! Case back dating ended in 1972, not 1974.

Below is a chart I put together a while ago from actual watches comparing their serial numbers to their case back dates.

SERIAL NUMBER CASE BACK DATE
112XXX, case back dated IV 55
223XXX, case back dated I 57
306XXX, case back dated III 57 (Sub 6536)
307XXX, case back dated III 57 (6538)
349XXX, case back dated I 1958
355XXX, case back dated II 1958 (GMT 6542)
360XXX, case back dated II 1958 (Sub 5508)
381XXX, case back dated II 1958
381XXX, case back dated I 1958 (Sub 5510)
397XXX, case back dated III 1958 (GMT 6542)
398XXX, case back dated II 1958 (GMT 6542)

398XXX, case back dated III 1958(GMT)6542)
399XXX, case back dated I 59 (SUB 6536)
400XXX, case back dated III 1958 (SUB 5508)
427XXX, case back dated IV 1958 (GMT 6542)
488XXX, case back dated III 1958(Sub 5508)
489XXX, case back dated III 59
490XXX, case back dated III 59
503XXX, case back dated I 60 (GMT)
547XXX, case back dated II 60
577XXX, case back dated II 60
596XXX, case back dated IV 60
624XXX, case back dated IV 60 (Gilt GMT)
661XXX, case back dated I 61 (Sub 5512 4-liner)
6959XX, case back dated II 61 (GMT 1675)
745XXX, case back dated II 62
87XXXX, case back dated IV 62 (Sub 5512)
87XXXX, case back dated I 63
876XXX, case back dated I 63 (GMT 1675)
87XXXX, case back dated IV 63 (Gilt GMT)
989XXX, case back dated III 63 (Sub 5513)
990XXX, case back dated III 63
997XXX, case back dated III 63
10XXXXX, case back dates III 64
10XXXXX, case back dated III 63 (Sub 5513 w/5512 case back)
10XXXXX, case back dated IV 63
104XXXX, case back dated IV 63
112XXXX, case back dated IV 64
11XXXXX, case back dated IV 64 (Gilt GMT 1675)
116XXXX, case back dated I 65
120XXXX, case back dated I 65 5513 Submariner
127XXXX, case back dated IV 64
1299XXX, case back dated II 65 (GMT 1675)
13XXXXX, case back dated IV 65
13XXXXX, case back dated II 65 (gilt GMT)
133XXXX, case back dated I 66
134XXXX, case back dated III 66
137XXXX, case back dated I 66
140XXXX, case back dated II 66 (gilt GMT)
14XXXXX, case back dated II 66
14617XX, case back dated II 66 (Gilt GMT 1675)
142XXXX, case back dated IV 65 (Gilt GMT sold 9/67)
15XXXXX, case back dated III 66 (Sub 5513)
153XXXX, case back dated II 66 (GMT 1675 gilt)
15XXXXX, case back dated VI 66 (model 1016, 6th qtr)
15XXXXX, case back dated VI 66 (model 6466, 6th qtr)
16XXXXX, case back dated II 67 (GMT, Mark I dial)
160XXXX, case back dated II 67
163XXXX, case back dated II 67 (one owner GMT full set)
164XXXX, case back dated II 67
168XXXX, case back dated II 67
170XXXX, case back dated II 67
17XXXXX, case back dated II 67
17XXXXX, case back dated IV 67
171XXXX, case back dated IV 67
177XXXX, case back dated IV 67 (Sub 5513)
179XXXX, case back dated II 67 (GMT 1675)
180XXXX, case back dated I 68
18XXXXX, case back dated I 68 (GMT 1675)
182XXXX, case back dated II 67
182XXXX, case back dated IV 67
18XXXXX, case back dated IV 67
18XXXXX, case back dated IV 67
183XXXX, case back dated I 68
185XXXX, case back dated IV 67
1852XXX, case back dated I 68
188XXXX, case back dated I 68
18XXXXX, case back dated I 68
18XXXXX, case back dated III 68
19XXXXX, case back dated III 68
19XXXXX, case back dated III 68 (GMT)
1902XXX, case back dated III 69
194XXXX, case back dated III 68
19XXXXX, case back dated IV 68
19XXXXX, case back dated IV 68
194XXXX, case back dated IV 68
204XXXX, case back dated IV 68 (sold 3/70)
2043XXX, case back dated III 68 (GMT 1675)
206XXXX, case back dated IV 68
209XXXX, case back dated IV 67
211XXXX, case back dated IV 68 (GMT, sold 8/13/71)
213XXXX, case back dated IV 68
21XXXXX, case back dated II 69
218XXXX, case back dated I 69
21XXXXX, case back dated I 69 (Submariner 1680)
22XXXXX, case back dated II 69
231XXXX, case back dated I 71
231XXXX, case back dated III 69
23348XX, case back dated IV 68 (GMT 1675)
23346XX, case back dated II 71 (GMT 1675)
2355XXX, case back dated III 69 (red Sub 1680)
23XXXXX, case back dated IV 70
24XXXXX, case back dated IV 69
24XXXXX, case back dated IV 69
24XXXXX, case back dated II 70
241XXXX, case back dated III 69 (red Sub)
241XXXX, case back dated I 70 (red Sub sold 7/71)
24XXXXX, case back dated I 70
242XXXX, case back dated II 70 (GMT Mark I dial)
244XXXX, case back dated II 70
247XXXX, case back dated II 70
25XXXXX, case back dated I 70
2556XXX, case back dated II 70
250XXXX, case back dated I 70
26XXXXX, case back dated III 70
267XXXX, case back dated I 70
27XXXXX, case back dated I 70 (Sub 1680, sold 8/26/72)
271XXXX, case back dated I 70
276XXXX, case back dated III 70 (GMT 1675)
2817XXX, case back dated I 70 (GMT 1675)
272XXXX, case back dated II 71 (Datejust 1603)
27XXXXX, case back dated II 71 (GMT)
281XXXX, case back dated II 71
28XXXXX, case back dated III 71 (1600 Datejust)
28XXXXX, case back dated IV 70 (red Sub sold 6/1974)
284XXXX, case back dated II 71 GMT 1675
286XXXX, case back dated II 70 (SS/14k GMT 1675)
28XXXXX, case back dated IV 70
2906XXX, case back dated II 71 GMT Mark II dial
29XXXXX, case back dated III 70 (Sub 5513)
292XXXX, case back dated IV 70 (Sub 1680)
29XXXXX, case back dated I 71
292XXXX, case back dated II 71
2961XXX, case back dated II 71 (GMT 1675/set)
297XXXX, case back dated II 71
29XXXXX, case back dated I 72 (Explorer)
304XXXX, case back dated II 72
307XXXX, case back dated III 71
30XXXXX, case back dated III 71
309XXXX, case back dated I 72
31XXXXX, case back dated II 71
315XXXX, case back dated II 71 (GMT 1675)
323XXXX, case back dated I 72
32XXXXX, case back dated II 72
3245XXX, case back dated II 72 (GMT/1675-SS)
3266XXX, case back dated II 72 (GMT Mark II)
330XXXX, case back dated IV 72 (Sub 1680)
33XXXXX, case back dated II 72
33XXXXX, case back dated III 72
33XXXXX, case back dated IV 72
3382XXX, case back dated II 72 (GMT)
34XXXXX, case back dated II 72 (GMT 1675)
3425XXX, case back dated III 72 (GMT 1675 set)
35XXXXX, case back dated I 72
36XXXXX, no case back date
374XXXX, no case back date
380XXXX, no case back date
386XXXX, case back dated I 72
6167XXX, --------------- (1980 Sub 1680, VE clasp code)

[Old Expat Beast]

Originally Posted by mjolnir2thor

Thank you for the response. It makes good sense to me!

I was unaware that these lists are not official from Rolex but from 3rd parties. Probably collected and then compiled into the tables I am finding on the Internet. That explains a lot! Appreciate it!

The most comprehensive table is this crowd-sourced one at VRF: http://vintagerolexforum.info/vrf/index3.html

[Dan S]

Originally Posted by springer

Below is a chart I put together a while ago from actual watches comparing their serial numbers to their case back dates.

And thank you for gathering and posting that info, JP. I reference it often.

[Haywood_Milton]

Thanks to Filipão for sharing his Rolex correspondence.

One wonders how reliable some of the answers are. For example, 5508-762976 is part of a consecutive batch of over one thousand examples of the same model, all others of which in my records have II.62 case-backs. This would not be consistent with manufacture in 1961.

Insta : haywood_milton_rolex

[Filipão]

Originally Posted by Haywood_Milton

Thanks to Filipão for sharing his Rolex correspondence.

My pleasure.

Hopefully correct...

[mjolnir2thor]

Thank you everyone for the wealth of information. Much appreciated!

[swish77]

Originally Posted by springer

Below is a chart I put together a while ago from actual watches comparing their serial numbers to their case back dates.

Great list! I've seen watches as late as 4 million with dated case backs. Here's a case back from a 5514 Sub (with correct 5513 back and engraved serial.)

This would be an especially tough watch to date. Do you go by case back date or serial number?

[JohnBaker3]

Hey Guys;

Great thread because it totally points out the dilemma of trying to reverse engineer the manufactured dates of these watches...

As pointed out, ROLEX could help us out but has decided in their infinite wisdom to just keep us guessing!

About 8 years ago I took it upon myself the challenge to track down as many databases that I could and combine them into a useable document; in fact I found 8 different sources and came up with the attached spreadsheet...

I don't think anyone mentioned that some watches still have the original invoice for their Rolex; Interestingly, many watches purchased back in the 60's and 70's were drifting around the pipeline for over 2 years! But, my last purchase in 2018 was at the AD's for less than 20 minutes from the time they received it from ROLEX!

Bottom Line: Use lots of grains of salt trying to date your watch's date of manufacture; but have a good time while doing it!

[mjolnir2thor]

Originally Posted by JohnBaker3

Hey Guys;

Great thread because it totally points out the dilemma of trying to reverse engineer the manufactured dates of these watches...

As pointed out, ROLEX could help us out but has decided in their infinite wisdom to just keep us guessing!

About 8 years ago I took it upon myself the challenge to track down as many databases that I could and combine them into a useable document; in fact I found 8 different sources and came up with the attached spreadsheet...

I don't think anyone mentioned that some watches still have the original invoice for their Rolex; Interestingly, many watches purchased back in the 60's and 70's were drifting around the pipeline for over 2 years! But, my last purchase in 2018 was at the AD's for less than 20 minutes from the time they received it from ROLEX!

Bottom Line: Use lots of grains of salt trying to date your watch's date of manufacture; but have a good time while doing it!

From what I learned, the case back date (e.g., iii.63) is the only real hint you get in regard to dating of a 1972 and earlier timepiece. Really kind of sad that Rolex removed the casebook date from their manufacturing process. Although, it sure gives us topics to discuss on the RF!