Is there a widely recognized "fake SSN for testing" that is conventionally understood as not a real Social Security Number?

General Discussions
#1

Is there a widely recognized “fake SSN for testing” that is conventionally understood as not a real Social Security Number?

#2

The Social Security Administration (SSA) explicitly states in this document from their website that using “000” as the first group of numbers will “NEVER be a valid SSN”. This is considered definitive information from the SSA.

However, regarding the second or third groups of numbers, it can be inferred from an FAQ published by the SSA that allocations start from “01” or “0001”. Although it’s not explicitly stated that “00” or “0000” will never be used, another FAQ clarifies that “00” or “0000” will indeed never be assigned:

There isn’t a reference to the advertisement reserved SSNs on the SSA site, but it appears that no numbers starting with a three-digit number higher than 772 (as referenced in the first document) have been assigned yet. However, there’s no explicit statement from the SSA that those numbers are reserved.

The Wikipedia information on advertisement reserved numbers is widespread, although its source is a book not readily accessible. Having an official citation from the SSA would clarify this, especially now that the concept is widely known.

The SSA website does include stories about retired SSNs due to their use in advertisements or samples, but there isn’t a clear link to their current policy on this:

This information helps ensure clarity when using a “fake SSN for testing” in various contexts.

#3

You can use placeholder values. While there isn’t a universally recognized “fake SSN for testing,” many developers use placeholder values like “123-45-6789” or “999-99-9999” in non-production environments.

These numbers are well-known within the developer community to represent placeholders and are not valid SSNs.

#4

Some developers generate custom SSN-like values for testing purposes, ensuring they adhere to the format without being real SSNs.

For example, “000-12-3456” or “987-65-4321” are commonly used in tests where specific formats or edge cases need to be validated without relying on actual personal data.