When Was It Made?
Serial numbers are critical to the process of learning about the age of your Burroughs. The information below will help you to find dates of the early Class 1 and 2 (high keyboard) machines. At the very end is information about the Class 8 and 9 (Portable) adding machines. Locating the serial number is generally easy to do. Follow these guidelines:
High Keyboard machines - lower front just below the case lock key hole.
Low Keyboard machines - lower front just below the case lock key hole.
Portable Adding Machines - usually on the green keyboard plate, at the bottom center, just below the row of 1's keys. Some later model portable adders had the serial attached to the base of the machine, in the very front.
The manufacturing date of early Burroughs Class 1, 2, and 3 machines can be identified by the serial number on the front of the machine. You will also need to identify the model or style of the machine from the descriptions in the information provided. Generally, these machines had a prefix to the serial number that describes the model or style. So a serial number like 4-12762 would indicate a Class 1, Model 4 machine. Using the tables below, you can then identify the year of manufacture of your machine.
These table will only provide manufacturing date information if your machine was built before 1924. If your machine was built after that, you will notice that the serial numbers in the tables are smaller then your machine's serial. If that is the case, you will have to send a picture and the serial number to me, and I will be able to help you with a rough idea of the date. You can check below to see if your serial number is within the description and tables. If not you can write me. Write me at: Questions4Mike@burroughsinfo.com.
Note: The following tables cover the Class 1,2,3 machines only. If you have a Burroughs Portable Adding Machine, use the tables in the section following the Class 1, 2, and 3 machines.
This information about Burroughs serial numbering in the early years has been taken from the The American Digest of Business Machines (1924)
Serial Numbers (approx. 1915 to 1923) :
"The serial number is stamped on the front of the base of every machine. To provide against the possibility of any confusion in identifying early models from those of modern construction having similar model numbers designations, the serial numbers assigned to each of the early models are listed below in detail. It will be noted that the serial numbers of all early models are comparatively low -- in all cases less than 260,000 the approximate lowest serial number of machines with class designations.
Until 1914-1915, Burroughs machines were not numbered in sequence. The practice was to reserve a series of 1,000 to 5,000 numbers (more or less) and assign them to one model, and when that series was exhausted, a new set in a different series would be assigned. Thus, as will be noticed, a model will have several groups of serials numbers, sometimes in the same year of manufacture. The intervening numbers were assigned other models.
Dates of Manufacture
When the above plan of numbering was abandoned, a regular sequence was maintained. Each machine, regardless of its class or model, was assigned a consecutive factory number. The following table is an approximation of such serial numbers. The necessity of maintaining sale and consignment stocks of machines of various models often brings about a condition whereby a machine is not sold for many months after manufacture. Thus, it sometimes develops that, judged by actual date of sale, the following table will not appear correct. The dates shown below are believed to be the approximate dates of manufacture."
Serial Date Serial Date Serial Date
250,000 Sept 1914 550,000 Aug 1919 850,000 July 1923
300,000 May 1916 600,000 Dec 1919 900,000 Apr 1924
350,000 Feb 1917 650,000 May 1920 950,000 July 1925
400,000 Jan 1918 700,000 Dec 1920 1,000,000 Jan 1926
450,000 Aug 1918 750,000 Jan 1922 1,050,000 July 1926
500,000 Mar 1919 800,000 Nov 1022 1,100,000 May 1917
Chart for serial numbers prior to 1914
Courtesy of the Charles Babbage Institute, University of Minnesota, Minneapolis
Charts for serial numbers prior to 1915 (refer to model number):
Serials indicate the serial number range. Carriage type is the width of the carriage in inches. Manufacture year is the approximate year of manufacture (not sale).
Class 1, Model 1 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
1 - 2254 3 1/2 1895 - 1908
25288 - 25397 3 1/2 1906
25548 - 26000 3 1/2 1906
Class 1, Model 2 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
1 - 2254 3 1/2 1985 - 1908
25273 - 25287 3 1/2 1906
Class 1, Model 3 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
4011 - 6000 10 1/4 1898 - 1900
8000 - 17375 10 1/4 1900 - 1903
17500 - 19999 10 1/4 1907 - 1908
20000 - 24999 10 1/4 1903 - 1904
25089 - 25100 10 1/4 1905
25178 - 25214 10 1/4 1906
25223 - 25272 10 1/4 1906
25398 - 25547 10 1/4 1906
26000 - 34999 10 1/4 1904 - 1906
36000 - 47999 10 1/4 1906 - 1907
48000 - 49999 10 1/4 1908
50500 - 59999 10 1/4 1910 - 1911
Class 1, Model 4 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
60000 - 60200 2 5/16 1903 - 1906
60200 - 65000 2 5/16 1903 - 1906
110750 - 110999 Special 1909 - 1910
Class 1, Model 5 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
50000 - 50499 10 1/4 1903 - 1907
Class 1, Model 6 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
112000 - 112499 2 5/16 1908
112500 - 112549 10 1/4 1908
112550 - 112649 12 1/4 1908
112650 - 112749 10 1/4 1908
112750 - 112849 12 1/4 1908
112850 - 112999 2 5/16 1908
116000 - 116689 2 5/16 1908
116690 - 116849 10 1/4 1908
116850 - 116999 12 1/4 1908
123000 - 123999 18 1908
125200 - 125299 12 1/4 1908
125300 - 125699 2 5/16 1908
125700 - 125749 10 1/4 1908
132000 - 132499 2 5/16 1908
132946 - 132949 2 5/16 1909
132950 - 132999 10 1/4 1909
138000 - 138299 2 5/16 1909 - 1910
138700 - 138899 2 5/16 1910
138975 - 138999 12 1/4 1910
150200 - 150247 2 5/16 1910
150293 - 150399 2 5/16 1910
150600 - 150799 2 5/16 1910
150853 - 150854 18 1910
150855 - 150999 2 5/16 1910
151171 - 151211 18 1910
151300 - 151899 18 1910
151900 - 151999 2 5/16 1910
157000 - 158699 18 1910
Class 1, Model 6X (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
125000 - 125199 2 5/16 1909
125750 - 125999 2 5/16 1909
132500 - 132945 2 5/16 1909
138300 - 138699 2 5/16 1910
138900 - 138974 2 5/16 1910
150000 - 150199 2 5/16 1910
150248 - 150292 2 5/16 1910
150400 - 150599 2 5/16 1910
150800 - 150852 2 5/16 1910
151000 - 151170 2 5/16 1910
151212 - 151299 2 5/16 1910
155000 - 156999 2 5/16 1910
210000 - 211999 2 5/16 1910
Class 1, Model 7 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
65001 - 65101 10 1/4 1905 - 1906
65500 - 65999 10 1/4 1906
66000 - 67999 2 5/16 1906 - 1907
68000 - 68499 12 1/4 1907
68500 - 69999 2 5/16 1907 - 1908
110000 - 111450 2 5/16 1908
111451 - 111549 10 1/4 1908
111550 - 111649 12 1/4 1908
111700 - 111799 12 1/4 1908
111800 - 111899 10 1/4 1908
111900 - 111983 12 1/4 1908
111984 - 111999 10 1/4 1908
115000 - 115149 12 1/4 1908
115150 - 115299 10 1/4 1908
115300 - 115499 2 5/16 1908
115500 - 115559 12 1/4 1908
115560 - 115599 10 1/4 1908
115600 - 115699 12 1/4 1908
115700 - 115799 10 1/4 1908
115800 - 115999 12 1/4 1908
122000 - 122999 18 1908
124000 - 124299 12 1/4 1908
124300 - 124399 10 1/4 1908
124400 - 124549 2 5/16 1909
124550 - 124699 10 1/4 1909
124700 - 124799 12 1/4 1909
124800 - 124999 2 5/16 1909
133000 - 133299 2 5/16 1909 - 1910
133300 - 133499 18 1910
133500 - 133599 10 1/4 1910
133600 - 133699 2 5/16 1910
133700 - 133999 18 1910
139000 - 138299 18 1910
139300 - 139399 2 5/16 1910
139400 - 139599 18 1910
139600 - 139699 2 5/16 1910
139700 - 139999 18 1910
152000 - 142999 18 1910
153200 - 154999 18 1911 - 1912
191000 - 194999 18 1912 - 1913
Class 1, Model 9 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
35000 - 35584 10 1/4 1905 - 1906
80000 - 80064 10 1/4 1905 - 1906
80200 - 82199 10 1/4 1906
82200 - 86999 12 1/4 1906 - 1907
87000 - 89499 10 1/4 1907
89500 - 89999 3 1/2 1907
100000 - 107999 10 1/4 1907 - 1908
108000 - 109999 12 1/4 1908
113000 - 114999 10 1/4 1908 - 1909
117000 - 119999 12 1/4 1908 - 1909
120000 - 121999 18 1908
126000 - 126999 12 1/4 1909
128000 - 128999 10 1/4 1909
129000 - 131999 18 1909
134000 - 137999 18 1909 - 1910
140000 - 137999 18 1910
159900 - 159999 18 1914
160000 - 179999 18 1911 - 1913
255000 - 255999 18 1914
Class 1, Model 11 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
90000 - 90999 12 1/4 1906 - 1909
91000 - 92999 18 1908 - 1910
93000 - 94999 18 1911 - 1912
212000 - 214999 18 1912 - 1913
248000 - 254999 18 1914
Class 1, Model 13 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
70000 - 70220 ? 1905 - 1906
70300 - 70310 10 1/4 1906
70500 - 70999 10 1/4 1906
71000 - 71400 12 1/4 1906 - 1908
71500 - 71999 18 1908
72000 - 72099 12 1/4 1909
72100 - 72999 18 1910 - 1912
99000 - 99999 18 1912 - 1913
110500 - 110749 Special 1908 - 1910
158700 - 159877 18 1914
Class 1, Model 15 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
75000 - 75269 ? 1905 - 1906
75400 - 75436 10 1/4 1906
75600 - 76099 10 1/4 1906
76100 - 77999 12 1/4 1906 - 1909
78000 - 79999 18 1908 - 1910
95000 - 98999 18 1909 - 1912
Class 1, Model 17 (first digit of serial number)
Serials Carriage Type Width in Inches Manufacture Year
73000 - 74999 18 1910 - 1912
230000 - 231999 18 1913 - 1914
Manufacturing Dates for Burroughs Portable Adding Machines
The Burroughs "Portable" Adding Machine (Class 8 and Class 9) was introduced in 1925-6 became the basic design for the adding machines for many years until the Burroughs Series J ten-key adder was introduced and started to gradually replace it.
Determining the date of a Class 8 or 9 adding machine is difficult because serial number to date tables are difficult if not impossible to find. There are a number of construction changes that do help to identify an approximate date range as shown below.
Early portable machines - 1925 - Class 8. The basic adder was black in color with a green keyboard base plate. It had round keytops and did NOT have subtract capability. It used an all black ribbon, and was first released in hand operated models only. The case of the machine is secured in the front with a single screw, and generally the decal in the front reads "Burroughs Portable".
First Subtract Design - 1928 - Class 9. This model now had subtract capability. The first subtract mechanism was a metal lever which came through the keyboard top plate in the lower right corner of the keyboard. The level was pushed toward the top of the keyboard to set up a subtract operation.
First Electric Design - 1930 - Class 8, 9, 10. The adders became available in both the traditional, hand-operated models and now an electric model. The machine came with a handle (as power supplies in many areas were not reliable).
First Two Total Design - 1930 - Class 10. The portable adder now included a new model, the Class 10 machine. The primary difference was the addition of a second totaling register. These machines became very popular as "teller" machines in banks. Many models were made over the years. They were normally built with many features needed by banks such as locked paper rewind, check or receipt printing capability, numbering features, multiple totals, rotary date stamp feature, keyboard protection column covers, etc. Later models of the Class 10 machines were also used as Cash Registers, or Cash Machines as Burroughs called them.
New Subtract Design - 1934 - Class 9. In about 1934, the level subtract design was changed to a large key on the right edge of the keyboard.
Army Colors - 1941 - Class 8, 9. During the war years the machines were painted a khaki color at first and later an army green. These machines were often sold to the military, but not exclusively. Some featured special mechanisms to make the machines more rugged or safer to use in demanding conditions.
Square Keytop Design - 1945 . The traditional round keytops were replaced with more modern style square keys and the color of the machines changed from black to a dark brown with a rough finish.
New Light Colors - 1949 . The color of the portable changed to a light brown color about this time.
New Case Design - 1954 . The case of the portable was completely changed to a smooth rounded case.