SOUNDEX()

SOUNDEX returns a four-character code to evaluate the similarity of two strings.

Signature

SOUNDEX ( character_expression )

Parameters

  • character_expression — An alphanumeric expression of character data. *character_expression* can be a constant, variable, or column.

Examples

SELECT SOUNDEX('Smith') AS smith, SOUNDEX('Smyth') AS smyth;
smith smyth
----- -----
S530  S530
SELECT SOUNDEX('Smith'),
       SOUNDEX('Smythe');
S530|S530

Run against SQL Server 16.0.4265.3 on 2026-09-13. This is the output we got, not the documentation’s.

Available on

  • SQL Server 2017 and later
  • Azure SQL Database
  • Azure SQL Managed Instance
  • Azure Synapse Analytics
  • Analytics Platform System (PDW)
  • Microsoft Fabric warehouse
  • Fabric SQL database

Signature and description adapted from the Microsoft SQL documentation, used under the CC BY 4.0. SQL Server and Azure are trademarks of the Microsoft group of companies. This page is not affiliated with Microsoft.