Here's hoping you live a long and healthy life, happily spending every dime that you so painstakingly accumulated in your retirement accounts.

But it might not work out that way. Not everybody gets to the retirement finish line. And while your premature death would be (one hopes) a blow to your loved ones, a mishandled transfer of your 401(k) account would add more than insult to the injury of losing you:

• Your money could wind up going to the wrong people.

• A big chunk of it could be claimed, unnecessarily, by Uncle Sam.

Here's what you need to know to keep your 401(k) in the right hands if you're not there to supervise.

Old decisions can come back to haunt

If you're married when you die, then by federal law, your spouse is entitled to inherit your 401(k) unless he or she signed a waiver giving up that right, estate-planning attorney Burton Mitchell says. That's true even if you identified someone else when you filled out the paperwork to start contributing to the plan.

The exception is if you're part of a same-sex couple. Federal law doesn't recognize same-sex marriages, so your spouse wouldn't have automatic inheritance rights.

If that's the case, or if you're not married, the money in your account would be handed over to the person or people you listed as beneficiaries when you signed up.

Remember way back then? Maybe you identified the person you were married to at the time or a cousin you now haven't spoken to in years. Problem is, what you said back then goes, even if your circumstances have changed dramatically and you'd rather someone else inherited the money.

Naming children as beneficiaries can be tricky as well. If the kids are minors when you die, a court may not let them have the money outright and may name a trustee — which could be your ex-spouse if you're divorced. If you want to have control over who manages the money, you'd be smart to have a will or a living trust drawn up that creates a separate trust for the kids, then name that trust as the beneficiary.

Tax-deferred status is not automatic

Generally speaking, you want 401(k) money to stay in its tax-deferred wrapper as long as possible. Given enough time, even a small account can grow to impressive proportions if it's not taxed.

That's true after you die as well. If your heirs can keep their hands off the money, there are strategies to help it grow — and mistakes that will make it shrink fast. The scenarios:

Scenario 1: You're in a federally recognized marriage. Your surviving spouse can roll your 401(k) money into his own individual retirement account, said Roger Stinnett, a tax and financial planning manager for City National Bank. That's good, Stinnett said, because then he can opt to delay withdrawals until the year after he turns 70 1/2. (Remember, the longer the money remains tax-protected, the better.)

But your surviving spouse can still blow a good thing. If he accepts the money himself, rather than arranging a direct transfer into an IRA, your employer has to withhold 20% for taxes. And if he spends the money, it all becomes taxable, and taxes can eat up one-quarter or more of the total.

Scenario 2: You're not in a federally recognized marriage. In the bad old days, beneficiaries other than surviving spouses couldn't roll inherited 401(k) money into IRAs. They typically had to withdraw the money within five years, paying income taxes on the proceeds.

Fortunately, President Bush signed a pension-protection law in 2006 that changed that. Now children, unmarried partners and other nonspouse beneficiaries can roll 401(k) money into what's called an inherited IRA, set up for just this purpose. Nonspouse beneficiaries still have to take withdrawals from these IRAs, Stinnett said, but the withdrawals are based on the beneficiaries' life expectancies. The younger they are, the smaller the required withdrawal and the longer the bulk of the money can remain tax-protected.

There are some flies in the ointment:

• There's a deadline. The money has to be moved to the inherited IRA before the last day of the year after the year in which the account owner died. So if you die in 2009, your heirs would have to transfer your money to an inherited IRA by Dec. 31, 2010. If your heirs failed to make the deadline, they could still transfer the cash to an IRA, but they'd have to withdraw the money and pay taxes on it under the old 401(k) guidelines, which typically means within five years.

• The money should be transferred directly. As with surviving-spouse transfers, employers will withhold 20% of the money if beneficiaries receive it directly. They should arrange a direct transfer from the 401(k) into a properly titled inherited IRA. (If there are any questions about titling, consult a tax professional.)

You won't have much control over what your heirs do once you're gone, of course. But if you care about what happens to them and your money, you might want to discuss these issues with them and find a tax pro or an estate-planning attorney who can advise them when you're gone.

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