You are deep into your genealogy research and coming across documents that show a code like T650 instead of a surname? What does the code mean? Well, it’s a code from the Soundex phonetic system, used to index surnames.

Many American archival records have been indexed using this system. It’s a way to search surnames while ignoring minor differences in spelling. The code uses the first letter of the surname, followed by three numbers associated with the sound of the name. Letters of the alphabet are assigned a number (0 to 9). Vowels (A, E, I, O, U and Y) and the letters H and W are ignored. Also, if the same letter occurs twice in a row in the name, it is counted only once (e.g., Lloyd becomes Loyd). If there are fewer than 3 letters in the name, 0 is used for the last digit.

Examples:

SMITH = S530
TREMBLAY/TROMBLEY/TRIMBLE/TRUMBLE = T651

To help you identify different spellings of surnames, we suggest that you use the following Soundex indexing site: Avotaynu Consolidated Jewish Surname Index. It can also be used for non-Jewish surnames. To help you identify the Soundex code, you can use the JOS Soundex calculator.