Had Roger Ma not happened to check an old account, he may never have noticed that he and his wife were missing cash that was rightfully theirs.

In March, a couple of months after his wife left her job at Amazon, Ma, a certified financial planner in Washington, D.C., says he randomly logged into her old workplace 401(k) account. They’d rolled the account over to an individual retirement account in February, and yet, there was a pile of money sitting in it.

It turned out, her employer’s matching contribution had hit two months after her last day.

They aren’t the first family to (almost) leave money behind when leaving a job. As of July 2025, there were 31.9 million left-behind or forgotten 401(k) accounts, worth approximately $2.1 trillion, according to retirement account rollover firm Capitalize.

If you’ve recently left a job — either voluntarily or as the result of a layoff — your workplace retirement account is just one of the things worth double-checking, Ma wrote in a recent LinkedIn post: “Otherwise, you may end up leaving money behind without realizing it.”