Soundex Sorts Out Family Names

by Bob Brooke

When a genealogist looks for ancestors records, he or she soon discovers a confusing fact: Family names, or surnames, can be spelled many different ways. So how can a name be found if the researcher doesn't know the correct spelling? By using the sounds of the SOUNDEX.

An ancestor's surname may be Smith, Smyth, and Smythe on three different documents. Two brothers may spell their surnames differently--one named Li, the other Lee. Even simple surnames such as Jones can be spelled in various ways--Jhones, Jonnes, Uoans.

There are a number of reasons why there's so much confusion about surnames. For many years, names weren't standardized. Sometimes people didn't know how to write, so officials interviewing them made up letters to fit what they heard. At other times, the individual wasn't consistent in the way he spelled his own name. Finally, many people changed the spelling of their names to fit the country they were in.

These changeable names can make genealogical research difficult. The National Archives established SOUNDEX , which codes together surnames that sound similar but have different spellings, to index the U.S. censuses.

Under the SOUNDEX system, names are grouped together by sound rather than letter, which makes it possible to find names with the same sound, no matter how they are spelled. Many immigration records, some U.S. Census records, and a lot of other documents are indexed by SOUNDEX.

Every SOUNDEX code has a letter and three numbers. The first letter of SOUNDEX is always the same as the first letter in the surname. However, if a name was substantially changed or shortened after arrival in United States, an attempt should be made to find out the original name before searching early records.

SOUNDEX codes begin with the first letter of the surname followed by a three-digit code that represents the first three remaining consonants. Now look at the SOUNDEX code:


  1. BPFV
  3. DT
  4. L
  5. MN
  6. R
Ignore the letters A, E, I, 0, U, W, Y, and H.

Let's take the name Johannson. The first letter of the name always remains the same. So the first SOUNDEX space in this case is filled with J. Go through the name, crossing out those letters SOUNDEX tells you to ignore:
J 0 4/1 ~ N N SO N

If you have any double letters, treat them as one letter. For the NN in Johannson, for example, cross out one N.
J 0 $ ~ $ N SO N

Finally, fill in the other three SOUNDEX spaces with the numbers that represent the remaining letters:
J 0 $ $ N SO N SOUNDEX code: J525

No matter how many letters there are in the name, every Soundex code is made up of one letter and three numbers. So, J 525 is the number you will use to look through the Soundex index for the name Johannson. This code would also work for Johanson, Johnson, and Johnsson, among other names. If different letters that are side by side have the same number, as they would in JACKSON (C K and S are all number 2), use the number only once.

If the name code ends up shorter than the required one letter and three numbers, zeros must be added to the code. For example, Lee, which translates to L, would become L000. If the surname has different letters side-by-side that have the same number in the SOUNDEX coding guide, they should be treated as one letter. For example, Pfister is coded as P-236 (P, F ignored, 2 for the S, 3 for the T, 6 for the R).

If there's a prefix in a name, such as van der Horst or de Mornay, figure out the SOUNDEX code both with and without it. Try "Mornay" and "deMornay." Documents may be filed under either name. (MAC and MC aren't considered prefixes, so those names will be coded only as M or M000).

Finally, to use the index: When looking up Johannson, go to the J525 names and begin searching alphabetically by first name. In other words, Alice Johnson will be listed among the first J525s. Zachary Johanson will be among the last J525s. Above all, double-check the results. It's important to be sure it's the right code.

To use the census SOUNDEX to locate information about a person, his or her full name and the state or territory in which he or she lived at the time of the census must be known. It's also helpful to know the full name of the head of the household in which the person lived because census takers recorded information under that name.

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