How Social Security Numbers Can Help With Family History Research

One of the most valuable tools for me in researching my family members in the U.S. has been the Social Security Administration. Today I want to briefly explain why that is and how you might be able to learn an ancestor’s social security number (and what knowing that can tell you).

First, I should note this won’t help you in researching living family members, or even recently deceased in many cases. This is more for researching a couple of generations back.

The Social Security Death Index

If you already know your ancestor’s social security number, you can use it to search the social security death index. You can also search this index by name for free at

If you have an idea of where they died, you might be able to find them here. If you do, the record will confirm their birth date and death date, possibly a middle initial, their last place of residence (the town and zip code, not the home address), and their age at their death.


Application for a Social Security Number

While the death index has proven useful for me in confirming dates, or giving me more specifics when I only knew vaguely when a relative had passed away, I’ve found this resource far more valuable. It’s the SS-5 form, or application for a social security number.

This is not a free resource. You’ll need to provide as much information as possible in your request (here’s the form). The fee ranges from $21.00 – 27.00, and you can pay more for a certified copy if you need that for whatever reason. It’s been well worth the fee in my case.

While there are restrictions on what you can be given (depending on how long a relative has been deceased — read the rules here), I’ve used the SS-5 primarily to get an ancestor’s parents’ names when I couldn’t find them elsewhere.

One of the more interesting things I discovered when combining SSA records was a name change in the family.

My great-grandfather’s brother in Germany was locked up in Dachau by the Nazis. When he was finally, luckily, released he moved rather quickly to the United States and joined the service here. That led to a lot of records being available on him (whereas my great-grandfather has been terribly hard to trace because of towns and records being destroyed over there during the war).

I found his record in the death index, and had his SSN. So imagine my surprise when I ordered his SS-5 form, figuring it would give me his parents’ name — something I couldn’t find on the German side, and instead found a family name change.

His last name wasn’t Mattern. It was Weber. And it was still Weber when he applied for his social security number, so that’s what appeared on his application (as well as his parents’ names — no wonder I couldn’t find anything, right?). Knowing that, I was able to find even more military and immigration / travel records on his comings and goings before he changed his name.

It’s not a mystery I’ve completely solved yet. He changed his name in NYC, and it’s been a challenge trying to figure out which bureau he did that in, because you didn’t have to do it based on residence. And I still haven’t figured out what happened with the name in Germany. Did he and his brother change them together after the war (my grandfather was Mattern already when he came here to stay with his uncle)? Were they not really brothers after all? (Though they certainly look the part.) In trying to answer one question, I opened myself to even more.

But that’s the kind of thing your ancestors’ social security numbers (or just records from the Social Security Administration) can turn up. Don’t let them be an under-used resource.

Jenn is a professional writer and publisher, and the founder of Climb Your Family Tree.

She first became interested in genealogy as a teenager. Since that early start, she's spent 28 years putting her personal passion and professional research skills to use in exploring her own family history while assisting others in their genealogical journeys.

In addition to running Climb Your Family Tree, Jenn is a long-time PR, social media, and online marketing specialist and she's been a digital publisher / web developer for over 20 years. She owns a variety of web properties including All Freelance Writing, Freelance Writing Pros, Kiss My Biz, and NakedPR.

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