Bank accounts

Rick Law recommends sharing a list of all accounts and online log-in information with your family members so they can notify the bank of your death. "If nobody ever takes any more out or puts money in, it becomes a dormant account and then becomes the property of the state," he says.

Be sure to list any safe-deposit boxes you own, register your spouse or child's name with the bank and ask them to sign the registration document so they can have access without securing a court order.

Health care confidential

Possibly the most important health care document to fill out in advance is a durable health care power of attorney form. This allows your designee to make health care decisions on your behalf if you are incapacitated. The document should be compliant with federal health-information privacy laws, so that doctors, hospitals and insurance companies can speak with your designee. You may also need to fill out an Authorization to Release Protected Healthcare Information form.

If you are incapacitated and your family members can't locate a health care power of attorney, they will have to go to court to get a guardian appointed.

Porter Storey, executive vice president of the American Academy of Hospice and Palliative Medicine in Glenview, Ill., says it isn't enough to establish a health care power of attorney unless you have explained to your designee how you would like to be treated in case of incapacity. He also recommends writing a living will detailing your wishes.

Diane Dimond's mother had a series of strokes in 2006, and Dimond knew there was a signed living will tucked away in a safe at home. Dimond, 58 and living in New York, recalls the Sunday she watched her mother in a coma and was able to fulfill her wishes never to be kept on external life support. "It was gut-wrenching," she says, "but I took the physician aside and said, 'I want to take her home.'" Having her mother's living will enabled Dimond to do just that.

The living will and the power of attorney constitute what are called "advance directives"; some states consolidate these into a single form. (AARP offers a state-by-state listing of advance-directive forms on its website.) Terminally ill patients may wish to have their doctors sign a do-not-resuscitate order.

Certain companies, such as Advance Choice's DocuBank, will keep copies of health care documents for a fee. Subscribers get a wallet-sized card, and, in case of an emergency, a hospital will call DocuBank, which will fax over the information.

Life insurance and retirement accounts

Copies of life insurance policies are among the most important documents for your family to have. Family members need to know the name of the carrier, the policy number and the agent associated with the policy.

Be especially careful with life insurance policies granted by an employer upon your retirement, since those are the kind that financial planners most often miss, says David Peterson, CEO of Denver-based Peak Capital Investment Services. New York state alone is holding more than $400 million in life-insurance-related payments that have gone unclaimed since 2000, according to the state comptroller's office.

Estate planners also recommend that you draw up a list of pensions, annuities, individual retirement accounts and 401ks for your spouse and children.

An IRA is considered dormant or unclaimed if no withdrawal has been made by age 70½. According to the National Association of Unclaimed Property Administrators, tens of millions of dollars languish in unclaimed IRAs every year.

If your heirs don't know about these accounts, they won't be able to lay claim to them, and the money could languish. The U.S. Department of Labor estimates that each year tens of thousands of workers fail to claim or roll over $850 million in 401k assets. You can track unclaimed pensions, 401ks and IRAs at Unclaimed.com.

Marriage and divorce

Make sure your spouse knows where you have stored your marriage license. Mary Cay Corr, now 74 and living in Raleigh-Durham, N.C., couldn't locate hers when her husband died. "I had to write to New York, where we got married, and pay for a new marriage license to prove that I had been married to my husband before I could claim anything," she says.

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For divorced people, it is important to leave behind the divorce judgment and decree or, if the case was settled without going to court, the stipulation agreement, says Linda Lea Viken, president of the American Academy of Matrimonial Lawyers in Chicago. These documents lay out child support, alimony and property settlements, and also may list the division of investment and retirement accounts.

Include the distribution sheet listing bank account numbers that accompanied the settlement, to avoid disputes about ownership or payments due. Also include a copy of the most recent child-support payment order. In most states, the obligation to pay child support still exists after death.

Viken also recommends filing copies of any life insurance papers. In many states, if you have a policy that benefits your children, it can be set off against the ongoing child support.

You also should include a copy of the "qualified domestic relations order," which can prove your spouse received a share of your retirement accounts.