If you have a job and a 401(k), I'm going to assume you're smart enough to remember your pot of cash when you switch employers.

Unfortunately, taking your 401(k) with you isn't as easy as packing your Magic 8 Ball, Slinky and stapler into a nondescript cardboard box.

When it comes to dealing with a 401(k) from a former or soon-to-be former boss, you have four choices: Leave it alone; cash it in; transfer your money to your new employer's 401(k); or move the cash to an Individual Retirement Account.

Unless you anticipate a need to borrow from your retirement account, moving the money to an IRA is your best option. But doing it wrong could cost you.

When transferring cash from a 401(k) to an IRA, use a direct rollover to have your money sent from one financial institution straight to the other.

Any check made out from your 401(k) directly to you will come up short.

Companies are required to withhold 20 percent for taxes when writing checks directly to account holders trying to roll over funds. You wouldn't be able to get that money back until after filing your tax return for the year.

As an investor, that means you would have to come up with the missing 20 percent yourself to transfer the full amount of your old 410(k) into your new IRA. Or, you would be hit with withdrawal fees and taxes on the 20 percent of your nest egg that you won't be rolling over.

If you plan to eventually borrow from your 401(k) — to put a down payment on a house or pay off high-interest debt, you'll want to roll your old 401(k) into a new 401(k).

You can borrow from a 401(k) but not from an IRA. But remember: Once you borrow it, your cash won't be out working toward funding your retirement. Also, 401(k) plans generally offer fewer investment options.

If you're hoping to save yourself some effort by cashing in your account or simply leaving it where it's at, don't.

Leaving your 401(k) alone could mean you'll be charged administrative or other account management fees that would make your investment less profitable.

Cashing in your account — the worst option — would mean paying a 10 percent early withdrawal penalty. It also would mean paying the income taxes you got out of contributing to your retirement account on a pretax basis. And it would cut off a source of retirement cash.

That might sound OK when you drive your new convertible off the dealer's lot tomorrow, but you'll regret it when you're 68, broke, and living off of ramen noodles.

You've worked hard for the money in your 401(k). Don't let an upward career move mess up what you've achieved.

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