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Most married couples think about Social Security as two separate decisions. She files when she’s ready, he files when he’s ready, and together they figure it out. That independent approach quietly costs many couples hundreds of dollars every month, for the rest of their lives.
The rule at the center of this is the spousal benefit. A spouse is entitled to up to 50% of the higher earner’s benefit at full retirement age. That sounds simple, but the coordination piece is where couples go wrong.
The Mistake That Compounds for Decades
Here is what the mistake looks like in practice. One spouse claims at 62 and receives a reduced benefit of roughly $1,400 per month. The other waits until 67 and collects around $2,071 per month, which is close to the 2026 average for someone claiming at full retirement age. On the surface, this looks like a reasonable split.
The problem is that the lower-earning spouse’s spousal benefit gets permanently reduced when they claim early. Instead of receiving 50% of the higher earner’s full retirement age benefit, they lock in a smaller amount for life. Over a 20-year retirement, this coordination failure can cost the couple $800 to $1,200 per month compared to a well-timed strategy. That is a significant sum that simply disappears each year.
The Earnings Limit Trap
There is a second layer of risk for couples where one spouse is still working. In 2026, the earnings limit for anyone collecting Social Security before full retirement age is $24,480.. Exceeding it triggers an automatic benefit reduction of $1 for every $2 earned above that threshold. This penalty is steep enough that early claiming while still employed can wipe out much of the benefit entirely. A spouse earning meaningfully above the limit could lose thousands of dollars annually, making the combination of early claiming and continued work one of the most expensive Social Security mistakes a couple can make.
One Rule Most Divorced Spouses Never Use
A divorced spouse who was married for at least 10 years can claim benefits on an ex-spouse’s record, and it has no effect on what the ex receives. The ex does not get notified. Their benefit does not change. Yet most divorced people in this situation never file this claim, leaving a meaningful income source uncollected.
What to Do Before You File
The hardest-to-undo mistake in Social Security is claiming too early without mapping out how both spouses’ decisions interact. Before either spouse files, run the numbers on both claiming ages together, not separately. If one spouse is still working, check the earnings limit first. And if you were married for a decade or more, check whether an ex-spouse’s record opens a benefit you have been ignoring.
The rules here reward couples who treat this as a joint decision. The exact right answer depends on health, income, and age gaps, but the starting point is always the same: look at the full picture before anyone signs anything.