US Social Security Number (SSN) Regex for Go

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching us social security number (ssn), ported and verified for Go. Financial data validation has zero tolerance for false negatives — a missed invalid entry can corrupt downstream calculations. The snippet below is ready to drop into your Go project — whether you're validating in a Gin handler, a gRPC service, or a command-line tool.

Go Implementation

// US Social Security Number (SSN)
// ReDoS-safe | RegexVault — Finance > Tax & Registration

package validation

import "regexp"

var usSocialSecurityNumberSsnRe = regexp.MustCompile(`^(?!(?:000|666|9[0-9]{2})-)[0-9]{3}-(?!00-)[0-9]{2}-(?!0{4})[0-9]{4}$`)

func ValidateUsSocialSecurityNumberSsn(s string) bool {
    return usSocialSecurityNumberSsnRe.MatchString(s)
}

// Example
// fmt.Println(ValidateUsSocialSecurityNumberSsn("123-45-6789")) // true

Test Cases

When to use this pattern

This pattern is drawn from the Finance > Tax & Registration category and carries a ReDoS-safe certification. That matters for Go developers because Go's RE2 engine is inherently safe from catastrophic backtracking, but this pattern has been additionally verified for correctness. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

Invalid SSN ranges: 000-XX-XXXX (area 000), 666-XX-XXXX, 900-999-XX-XXXX. Group 00 and serial 0000 are also invalid. The pre-2011 geographic assignment pattern is no longer used.