Immigration and Ships Passenger Lists Research Guide
Section 2.4 - Last updated Sept  2011

Return to Main Table of Contents
Return to Section 2.0 - Getting Started

Section 2.4 - Guide to the Soundex System

American Soundex Codes

Many of the Indexes to the passenger lists use the Soundex system in listing the passenger's name. You must first find the Soundex code for your immigrant ancestor in order to use these indexes.

This system, which is also used for census indexes, keeps together names of the same and similar sounds but of variant spellings. To search for a particular name, you must first find the Soundex code number for the surname of the individual.

To find the Soundex code, you may use the "Soundex Calculator"

You can also find the code by following procedure.  Use the first letter of the surname -  No number is assigned to the first letter of the surname. If the name is Kuhne, for example, use "K''.  The following letters of the surname are replaced with numbers in accordance with the following guidelines.

 The first letter of the surname is retained and is followed by a three-digit code as worked out from the following equivalents.  The letters a, e, i, o, u, y, w, and h are not coded.

                       Soundex Coding Guide

Number Represents the Letters
1 B, F, P, V
2 C, G, J, K, Q, S, X, Z
3 D, T
4 L
5 M, N
6 R

 (The code number for Kuhne, worked out according to this system is K-500.)

Every Soundex number must be a three-digit number.  A name yielding no code numbers, as Lee, would  be L-000; one yielding only one code number would have two zeros added, as Kuhne, coded as K-500; and one yielding two code numbers would have one zero added, as Ebell, coded as E-140. Not more than three digits are used, so Ebelson would be coded as E-142, not E- 1425.

When two key letters or equivalents appear together, or one key letter immediately follows or precedes an equivalent, the two are coded as one letter, by a single number, as follows:

In the index, if several surnames have the same code, the index cards for them are arranged alphabetically by given name. There are divider cards showing most code numbers, but not all. For instance, one divider may be numbered 350 and the next one 400. Between the two divider cards there may be names coded 353, 350, 360, 365, and 355, but instead of being in numerical order they are inter filed alphabetically by given name.

Such prefixes to surnames as "van,'' "Von,'' "Di,'' "de,'' "le,'' "Di,'' "D','' "dela,'' or "du'' are sometimes disregarded in alphabetizing and in coding.

Other Soundex Coding Systems

The following systems of Soundex are being offered as options on a number of online sites.

Daitch-Mokotoff Soundex (D-M Soundex) is a phonetic algorithm invented as a refinement of the American Soundex algorithms.  It is designed to allow greater accuracy in matching of Slavic and Yiddish surnames with similar pronunciation but differences in spelling.

Beider-Morse Phonetic Name Matching Algorithm

To address the large number of false positive results generated by the D-M Soundex, the Beider-Morse Phonetic Name Matching algorithm. This new algorithm cuts down on false positives at the expense of some false negatives. A number of sites are offering the B-M soundex in addition to the D-M soundex.

Back to the top


Return to Table of Contents
Return to Section 2.0 - Getting Started

Copyright © Arnold H. Lang 2002