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Underwood 300R

Underwood 300R
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Underwood 300R

The Underwood 300R is an electric adding listing machine with a 10-key keyboard. It has a 9-digit register, and allows 8 digits of input. It has a 10-key pad for inputting numbers, extended by a 00 button.
There are four control buttons:

There also some control levers and switches:

Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R

The serial number is found on the bottom, and is 5,241,177. The top part of the casing is hinged and can be lifted up, giving access to the ink ribbon. The machine takes a standard half-inch wide two-colour ink ribbon. The casing is quite difficult to remove. The front edge has to be pulled forward so that it bends far enough for the tabs to clear their slots. The inside mechanism is essentially identical to the Olivetti Quanta 20.

Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R
Underwood 300R



Underwood is named after the entrepreneur John T. Underwood, who was born in London in 1857. His father ran an ink company there, but then moved his company and his family to New Jersey. They supplied ink ribbons to the Remington typewriter company. When Remington started making their own ink ribbons, John Underwood apparently decided to move into the typewriter business. In 1895 he bought Wagner Typewriter Company, a company that was founded three years earlier by Franz Xavier Wagner to manufacture a typewriter he designed. This company became the Underwood Typewriter company.

Wagner's design and its various improvements made Underwood the most successful typewriter company in the world. The Standard Model 5 typewriter was manufactured from 1900 till 1932, and millions were made. It set the standard for all typewriters that came after.

The Elliott-Fisher company made various specialist typewriting and bookkeeping machines. In 1927 they bought the Sundstrand Corporation, a maker of adding machines. That same year they merged with Underwood to become the Underwood Elliott Fisher company. The adding machines were sold using the brand Underwood-Sundstrand. In about 1946 the company name changed to the Underwood Corporation.

In 1959 Olivetti bought Underwood, and soon the range of models was merged. The new American Underwood adding machines were basically the same as the Italian Olivetti machines, except that they had different cases.


The model numbering during the Underwood-Sundstrand era (1927-1959) is a little unclear to me. The adding machines shown in the advertisements all look very similar, and are essentially the same as the machine that Sundstrand made before the take-over. It seems that they were given a model number that starts with the register capacity, ranging from 7 to 13. This is followed by three further digits, such as 100, 102, 120, 126, 140, 142, 240. It may be that this is then followed by a letter or digit suffix. On Recher Lexicon there is a list of serial numbers that I reproduce below:

YearSerial number
192570 000
192686 600
1927110 600
1928136 000
1929140 000
1930158 000
1931178 000
1932205 000
1933210 000
1934213 000
1935221 400
YearSerial number
1936235 800
1937275 000
1938289 000
1939293 000
1940325 000
1941340 000
1942355 000
1943372 000
1944423 000
1945451 000
1946475 000
YearSerial number
1947506 000
1948550 900
1949594 200
1950644 200
1951709 001
1953830 101
1954873 000
1956958 000
19571000 000
1959(1)220 000
1961(1)283 000

In 1958 a new model was introduced named the Add-Mate, though it actually had model number 782A (capacity 7×8) or 902A (capacity 9×10). This was a much more compact adding listing machine. It was also sold outside the US as the Piccolo Elektrik.

A few years after Olivetti took over, the Underwood adding machine models were discontinued, and replaced with new models that were essentially the Olivetti adding machines with a different case.

ModelCapacityYearOlivetti equivalentNotes
Underwood 100 8×9 1962-1971-Similar to the Add-Mate
Underwood 200 10×111962-1971Olivetti Summa 15Manual. The 4-way joystick button is replaced by two perpendicular levers.
Underwood 278,288 8×9 1962-1971Olivetti Summa Quanta 20Simplified: No input indicator, no undo last input digit
Underwood 300 10×111962-1971Olivetti Summa Quanta 20
Underwood 300R 8×9 1962-1971Olivetti Summa Quanta 20As 300 but reduced capacity
Underwood 400 12×131962-1971Olivetti Elettro Summa 22
Underwood 600 10×111965-1971Olivetti Multisumma 20
Underwood Multimaster 12×131965-1971Everest PlurimaticIn 1965 Olivetti took over Officine Serio, which made the Everest machines.


First a few ads for the early Underwood typewriters.

1896-10-15 Hartford Courant (Connecticut)
1904-01 Forestry and Irrigation
1904-11-05 The literary digest
1906-07 The international studio
1908-12 The international studio
1911-07 American Historical Review
1912-08 The Masses
1923-04 The international studio

A few ads for the Sundstrand adding machine, before Elliott-Fisher got involved.

1918-10-05 The literary digest
1918-10-19 The literary digest
1918-12-14 The literary digest
1919-03-22 The literary digest
1919-12-06 The literary digest
1921-03-05 The Saturday evening post
1922-10-21 The Saturday evening post
1922-11-18 The Saturday evening post
1923-04-21 The Saturday evening post
1924-08-09 The Saturday evening post
1924-09-24 The Saturday evening post
1926-10-09 The Saturday evening post
1926-12-11 The Saturday evening post

Here are ads for the Underwood-Sundstrand adding machines.

1934-01 Nation's Business
1934-05 Nation's Business
1934-10 Nation's Business
1936-06 Nation's Business
1937-06 Nation's Business
1937-07 Business
1937-09 Business
1937-10 Business
1937-10 Nation's Business
1937-12 Nation's Business
1938-01 Nation's Business
1938-03 Business
1940-04 Nation's Business
1940-06 Nation's Business
1940-10 Nation's Business
1940-11 Nation's Business
1941-04 Nation's Business
1941-06 Nation's Business
1941-09 Nation's Business
1941-11 Nation's Business
1943-06 Nation's Business
1944-06 Nation's Business
1944-12 Office Appliances
1945-09 Business
1947-03 American Business
1948-03 Nation's Business
1948-05 Nation's Business
1949-01 Business
1949-02 Business
1949-03 Nation's Business
1949-06 Business
1949-09 Business
1949-10 Nation's Business
1949-11 Nation's Business
1950-05 Nation's Business
1950-05 Office Appliances
1950-06 Nation's Business
1950-09 Business
1950-11 Nation's Business
1951-03 Business
1951-04 Business
1951-05 Nation's Business
1951-06 Nation's Business
1951-12 Business
1953-06 The Bridge
1954-02 Office Appliances
1954-04 Nation's Business
1954-06 Nation's Business
1954-09 Nation's Business
1955-05 Nation's Business
1957-05 Nation's Business

Lastly some ads for the later Olivetti-Underwood adding machines.

1965-09 Marketing Horizons
1971-02-28 Honolulu Star Bulletin (Hawaii)
1971-03-18 The Cincinnati Enquirer (Ohio)
1971-09-16 Newsday (Melville, New York)
1971-12-15 The Cincinnati Post (Ohio)


This is a small selection of the Underwood-Sundstrand patents.

PatentFiling datePublished dateNameDescription
US 2,004,49506-05-193311-06-1935Oscar J. Sundstrand & Underwood Elliott Fisher CompanyTransfer mechanism
US 2,021,61828-11-193219-11-1935Oscar J. Sundstrand & Underwood Elliott Fisher CompanyAdding machine
US 2,057,40005-07-193413-10-1936Oscar J. Sundstrand & Underwood Elliott Fisher CompanyNegative totals
US 2,088,98226-06-192603-08-1937Oscar J. Sundstrand & Underwood Elliott Fisher CompanyAdding machine
US 2,160,29631-03-193430-05-1939Oscar J. Sundstrand & Underwood Elliott Fisher CompanyNegative totals
US 2,204,23924-12-193811-07-1940Oscar J. Sundstrand & Underwood Elliott Fisher CompanyCalculator keyboard
US 2,267,88525-06-193730-12-1941Oscar J. Sundstrand & Underwood Elliott Fisher CompanyPrinting mechanism
US 2,308,29228-04-193912-01-1943Earle Marquess & Underwood Elliott Fisher CompanyAdding machine
US 2,309,28224-12-193826-01-1943Oscar J. Sundstrand & Underwood Elliott Fisher CompanyNegative totals
US 2,309,29225-06-193726-01-1943Walter A. Anderson & Underwood Elliott Fisher CompanyFractions
US 2,361,00230-12-194124-10-1944Walter A. Anderson & Underwood Elliott Fisher CompanyTax calculation
US 2,459,44120-12-193818-01-1949Walter E. Lippert & Underwood Elliott Fisher CompanyNegative totals


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