Couples have a key advantage over single adults when it comes to retirement planning. As long as one person worked long enough to qualify for Social Security retirement benefits, both will receive checks. This can significantly increase the cash available to these households, especially for those who weren't able to save a lot of money in their retirement accounts.

But planning for two Social Security checks also requires a bit more strategy if you want to maximize your household benefits. To do this effectively, all married couples need to know three important rules.

Smiling couple standing on steps looking out at nature.

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1. Spousal benefit eligibility requirements

People often think that you become eligible for spousal Social Security benefits on your partner's work record as soon as you get married, provided your partner qualifies for retirement benefits. But that's not actually true.

Typically, you must have been married for at least one year before you become eligible for spousal benefits, unless you're caring for your partner's minor or disabled child. You can also become eligible before a year is up if at the time of your marriage you were already eligible for Social Security benefits.

Some ex-spouses may also be eligible for spousal benefits if they were married to the worker for at least 10 years before divorcing. However, keep in mind that if you remarry, you lose the ability to claim benefits on your ex's work record.

2. How the government decides which benefit you get

If you're eligible for both spousal Social Security and retirement benefits, the Social Security Administration automatically gives you the larger of the two.

Your retirement benefit depends on your average monthly income over your 35 highest-earning years (adjusted for inflation), and your claiming age. You become eligible for your full benefit at your full retirement age (FRA), which is 66 to 67 for today's workers. You can claim as young as 62, but you'll get smaller checks for applying early. Delaying benefits beyond your FRA can grow your checks until you reach 70.

Spousal benefits work differently. Your maximum spousal benefit is one-half of your spouse's retirement benefit at their FRA. So if they're eligible for $2,000 per month at their FRA, you're eligible for a $1,000 monthly spousal benefit at your FRA.

Again, there are penalties for early claiming. These are even steeper for spouses than for workers. Workers only lose 5/9 of 1% per month for their first 36 months of early claiming while spouses lose 25/36 of 1% per month. However, you cannot grow spousal benefits past your FRA, so there's no incentive for waiting past this point.

3. When you can apply

You can claim retirement benefits in any month when you'll be at least 62 for the entire month. This means many who hope to sign up immediately may not be able to. Unless you were born on the 1st or 2nd of a month, you must wait until the month after you turn 62 to be eligible. And then you'll receive your first check in the following month. For example, if you turn 62 on Jan. 3, 2025, you can claim benefits beginning in February 2025 and you'll get your first check in March 2025.

Spousal benefits also have this age limitation, with the additional caveat that you cannot apply for benefits until your spouse is already claiming. There is an exception for divorced spouses. They can apply for benefits even if their ex isn't claiming, as long as they've been divorced for at least two years.

This makes it important to think strategically about when each person will claim and what type of benefit they'll likely receive. When both members of a couple have earned similar amounts throughout their lives, it's likely that both will claim their own retirement benefits. So it's often best for each person to delay claiming as long as possible to maximize their benefits, barring health or financial issues.

When one person has significantly outearned the other, it may be to the couple's advantage to have the lower earner claim early. Their checks can help the higher earner delay claiming until they qualify for a larger benefit. Then, when the higher earner applies, the lower earner can switch to their spousal benefit if it's worth more than what they're currently getting.

If you need help estimating how much each person will get from Social Security, try creating a "my Social Security" account. You'll have to verify your identity the first time you set it up. Once you're in, you'll be able to view your estimated monthly benefit at every claiming age, to help you make your decision.