One of the most popular areas in the porcelain telephone sign collecting field is the 11" x 11" porcelain signs with the 1921 logo of the Bell System. There were about 27 different companies that used this type of sign. Following are a list of the different companies grouped together in order of scarcity. This grouping is based on my own observations at shows, reading club publications and talking with other sign collectors. Of course, none of this is set in stone!

MOST AVAILABLE: New York Tel, Illinois Bell, Bell Tel of Penna. and Michigan Bell

SCARCE: Southwestern Bell, AT&T, Southern Bell, Mountain T&T, and Chesapeake & Potomac

VERY SCARCE: New Jersey, Southern California, Pacific T&T and Cincinnati and Suburban

RARE: Southern New England, New England, Citizens Tel, Ohio and Wisconsin 

VERY RARE: C&P of VA., C&P of W.V., C&P of Balto City, Northwestern Tel, Diamond State, Cumberland, Delaware & Atlantic Bell of Nevada