Phone Numbering & Naming

At one time, Western Electric picked a model number for a phone, and the other companies which made similar models used the same number.

A #500 single-line rotary phone is basically the same whether it's made by Western Electric, Stromberg-Carlson, ITT or Northern Telecom.

Here are two six-button touchtone wall phones. The one on the left was made by Western Electric. The one on the right is from Stromberg-Carlson. Both are model 2851.

Confusion works in the other direction, too. The model number for a Western Electric two-line rotary-dial phone with mechanical hold is 515. ITT and Stromberg-Carlson use #575 for the same type of phone.

The "Princess" name was a registered trademark of AT&T for the distinctive oval-base desk phone, but the name is frequently misused to identify other phones, most often the AT&T Trimline, as well as Princess clones produced by other companies, under license from AT&T:

  • "Cinderella" made by Kellogg, then ITT, now Cortelco.

  • "Petite" made by Stromberg Carlson, later renamed Comdial, now Vertical.

  • "Starlite" made by Automatic Electric for the GTE phone system (rectangular rather than oval)

  • "Contessa Phone" made by Northern Electric/Northern Telecom/Nortel. Early on in the production run they used a glue for the base pad that lost its adhesion after a few months. The base pads fell off of the phones when they were removed from their boxes, and the phone was referred to as the "barefoot contessa" (The Barefoot Contessa is a 1954 film about fictional Spanish sex symbol Maria Vargas. It was written and directed by Joseph L. Mankiewicz and stars Humphrey Bogart, Ava Gardner and Edmond O'Brien.)

  • Many reproductions from other companies, such as Crosley and Sonecor.

  • Some people call the "Trimline" the "Princess Trimline."

phone bottom markings

Most phones have markings on their bottoms that provide important, or useful, or merely interesting information.

Similar identification schemes were used by the major manufacturers. HOWEVER, sometimes the same number was used for different models made by different manufacturers; and some codes were not used by all makers.


The date code format varies, but should be pretty obvious, such as:


  • "9 (space) 82" for September, 1982

  • "1-70" for January, 1970

  • "82-10" for October, 1982

  • "3/78" for March, 1978

  • "82003" for January 3 (the third day of the year), 1982


It was common for phones made by ITT (and perhaps by other manufacturers) to be dated six months after the actual manufacturing month, assuming it would take up to six months for the phone to reach its ultimate customer. This way the customer assumed the phone was brand-new.


When a phone was taken out of service and refurbished to be provided to another customer, it got a new date, either with a stick-on label or with ink. The earlier date could be covered by the label or paint. When phones are refurbished, they usually include parts made at different times. Many individual phone components have dates on them. When a phone was refurbished as a different version of the original model, a label indicates the new version.


Model numbers are usually obvious, such as 500 for a common rotary-dial desk phone or 2565 for a six-button touchtone desk phone. Sometimes the number sequence also indicates the color, such as the "13" (beige) in the top-left photo.


Letters after the numerals indicated specific versions or features, such as:


  • M, for modular cords

  • G, polarity guard on touchtone phones

  • P, wall phone with modular plug on its back plate

  • W, Western Electric phones without Bell System markings, made for the military, railroads, or non-Bell phone companies

  • CS, phones owned rather than rented by customers

  • BA, standard ringer

  • LR, no ringer

The Trimline design is ubiquitous, with probably thousands of variations from hundreds of manufacturers, some licensed by AT&T, some not.

  • "Trendline" was the ITT/Cortelco version. It was initially identical to the Trimline, but has gone through many modifications. It was originally made in Mississippi, and now comes from China.

  • "Slenderet" was the Stromberg-Carlson/Comdial version.

  • "Styleline" was the GTE version. Although it had the same basic shape as the Trimline, it was bigger, clunkier, and uglier, as was usual with GTE adaptations of AT&T designs. It used a really weird cord connector. Strangely, GTE phone stores also offered the ITT Trendline.

  • "Contempra" and Contemprette" were dial-in-handset phones from Northern Telecom/Nortel, but were wedge-shaped, not rounded like the Trimline.