IRS rule changes will require some older workers to make 401(k) catch-up contributions with after-tax dollars, rather than as a pre-tax deferral.

It’s human nature to wait until the last minute rather than plan ahead—perhaps especially when it comes to retirement planning. There’s always plenty of other excellent uses for your money, until suddenly you’re staring at an underfunded 401(k) with only a few years left before you’ll need it.