Robert Brown|Do you qualify for spousal Social Security benefits? Here's how to find out.

Social Security spousal benefits are Robert Browndesigned to provide additional retirement income, particularly in situations where one spouse was the primary earner or earned a comparatively high level of income. Nearly 2 million Americans receive a spousal benefit, and while qualifying for one isn't exactly difficult, there are a few specific boxes that need to be checked before a spousal benefit can be paid.

Qualification 1: You're married to someone who qualifies for Social Security

In simple terms, Social Security spousal benefits exist to provide retirement income for couples for whom one spouse was the primary earner. So the first qualification is an easy one: At least one spouse in a married couple must be eligible for a Social Security retirement benefit, based on work history in employment covered by Social Security.

Qualification 2: You're at least 62 years old

Just like Social Security retirement benefits, you generally must be at least 62 to claim a spousal benefit. The same full retirement age applies, which is 67 for those born in 1960 or later, and just like retirement benefits, there is a reduction if you claim your spousal benefit before you reach full retirement age.

However, it's worth noting that unlike Social Security retirement age, spousal benefits are not increased if you wait beyond your full retirement age. So here's one Social Security tip you might not be aware of: If someone is planning to collect a spousal benefit on your work record, it's rarely worth waiting beyond that person's full retirement age to claim your benefit.

Qualification 3: Your spouse must be collecting a Social Security benefit

That last sentence brings us to the third qualification. To collect a spousal benefit, the primary earner must be collecting his or her own Social Security retirement benefit. This hasn't always been the case, but Congress closed a big loophole a few years ago.

Qualification 4: Your own Social Security benefit is less than your spousal benefit

As a final point, it's important to realize that a spousal benefit can be paid instead of a Social Security benefit based on your own work record. When you apply for Social Security, the SSA will calculate how much you'd be entitled to on your own, as well as how much you'd get based on your spouse's work record, and pay the higher of the two.

I saw this in action recently, as both of my parents are in the process of applying for Social Security. My mother was a stay-at-home parent to myself and my two younger siblings but started working on at least a part-time basis when she was in her 30s. As it turns out, a spousal benefit was still the higher of the two, but the calculation was closer than my parents thought it would be. The Social Security benefit formula is heavily weighted in favor of those who earned relatively low incomes throughout their careers, so in many cases married couples with a large income disparity are surprised to learn that the highest benefits are on their own work records.

How much will you get from a spousal benefit?

A spousal benefit can be as much as half of the higher earner's primary insurance amount (PIA), which is the amount that person would get if he or she started collecting Social Security at full retirement age. There are about 1.9 million people who receive a spousal benefit, with the average monthly benefit of about $912.

If you want to get a good estimate of what to expect, it could be a good idea for both you and your spouse to check your latest Social Security statement. Just create an account at SSA.gov, and you'll find a ton of valuable information, including benefit estimates that are based on your actual work record.

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