10/23/2026
What Happens to Your 401(k) When You Change Jobs?
The average person changes jobs a dozen times in a career. Every time, there's a 401(k) decision to make — and the most expensive option is also the most tempting.
You generally have four choices: leave it where it is, roll it into your new employer's plan, roll it into an IRA, or cash it out. Let's talk about that last one, because cashing out is where the damage happens.
Say you're 35 with $10,000 in an old 401(k) and you cash it out. First, the plan withholds 20% for federal taxes right off the top — $2,000 gone immediately. Then, because you're under 59½, you owe a 10% early withdrawal penalty: another $1,000. And the full $10,000 counts as taxable income, so in a 22% bracket that's $2,200 in income tax (with $2,000 already withheld toward it). You net roughly $6,800 of your $10,000 — and you've robbed your 65-year-old self of what that $10,000 would have become, which at a hypothetical 7% over 30 years is over $76,000.
A rollover, by contrast, costs you nothing in taxes or penalties if done correctly — a direct rollover from the old plan to the new plan or an IRA. The money keeps growing, uninterrupted.
So when you change jobs: don't cash it out, don't ignore it. Roll it over. And if you've got old 401(k)s from jobs past just sitting there, consolidating them is one of the simplest cleanups in personal finance.