There's little question that Social Security is a phenomenal system that helps millions of Americans during retirement. What makes it even better is that a wage earner's spouse is also entitled to benefits even if the spouse never worked outside the house.

But unlike the primary beneficiary, there are a handful of rules that dictate whether a person qualifies for spousal benefits. If you're wondering whether you make the grade, here are the four main factors:

1. You're at least 62 years old (this is the same threshold for a primary beneficiary).

2. You've been legally married to the primary beneficiary for at least one year.

3. Your own work history doesn't qualify you for larger benefits (in which case you'd just take those).

4. Your spouse has already filed to receive their own benefits.

As Motley Fool contributor John Maxfield discusses in the following video, so long as you satisfy this four-part test, then it's safe to assume that you qualify for spousal benefits under the Social Security program.