Dying with debt can prove costly ... for the survivors

When a loved one dies, it's normal to feel grief and sadness. At such times, the last thing you want to do is field calls from debt collectors. Some such debts might be your responsibility to deal with, but others might have nothing to do with you.

Given increasing longevity and the lack of retirement readiness, more seniors than ever are taking their debts to the grave with them. A 2011 study from the University of Michigan Law School found that people 65 and older are the fastest-growing segment of the population filing for bankruptcy.

And in a new twist, seniors are also swimming in student loans. According to the Government Accountability Office, student debt by people 65 and older rose by more than 600 percent between 2005 and 2013. It now stands at $18 billion.

"This is a very confusing area for people," said Gerri Detweiler, director of consumer education for Credit.com. "It's not their debt, but they're inheriting the situation."

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So more survivors are finding themselves having to untangle debts after their parents die.

There's no one-size-fits-all answer to when debts are your responsibility and when you're not on the hook. But here are some general guidelines that will help you be as informed as possible when speaking with debt collectors.

1. The estate pays off debts. Generally, family members are not responsible for any debts for someone who has died. Debts might need to be paid back, but that money has to come out of the person's estate, not your pocket.

"If your dad died, his estate is the only entity liable for that debt," said Don Ford, a board-certified estate and probate lawyer with Ford & Bergner in Houston.

As long as there's money in an estate, debts are repaid first. Then any remaining money goes to beneficiaries. There is an order to how debts must be repaid. Funeral expenses, taxes and secured debts are the top. Unsecured debts, such as credit cards, are near the bottom. If the estate does not have enough money to pay back all the debt, creditors are out of luck.

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Remember that jewelry, antiques and other valuables must all be added to the estate. You might be forced to sell some of them in order to pay back creditors.

Though debts are the estate's responsibility, there are times when the executor might be personally liable, said Martin Shenkman, an estate attorney in New Jersey. If an executor pays out beneficiaries from an estate before all the debts are settled, creditors could make a claim against that person personally.

"An executor is usually a family member, like an uncle, and they might find it hard to refuse when their relatives are asking for their share of the estate," Shenkman explained.

2. Creditors can't look outside the estate ... usually. Of course, the estate may not be the only money the deceased person left behind. There might be a life insurance policy and retirement accounts, such as individual retirement accounts and 401(k) plans. If those have named beneficiaries—not the estate but a person—then that money is not considered part of the estate and doesn't need to be used to settle debts, said Ford, the Houston estate lawyer.

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There is an exemption to this, noted Shenkman, and that's taxes. The Internal Revenue Service has significant leeway about going after money to repay taxes. However, for his part, Ford said he has never encountered a situation where the IRS has requested repayment from life insurance or retirement funds.

3. Cosignatories and joint owners are different. The above rule of thumb doesn't apply for any loans you've cosigned or on which you are a joint owner. Those are your responsibility.

"You don't inherit your parents' or your children's debts unless you guaranteed them," Detweiler said.

Keep in mind that loans or credit cards you cosigned years back may still be active.

"Think back to that old boyfriend you helped out once," said Maureen Richardson, a certified financial planner with Richardson Elite Financial Strategies. She suggests checking your own credit report periodically to make sure you're not still holding debt for someone who isn't in your life.

4. There are exceptions in community property states. The estate rule is an exception in community property states. (There are 10 of them: Alaska, Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington and Wisconsin.) Debts that were incurred by one spouse for the benefit of the family are considered to be the property of the family. Therefore, spouses must pay them back.

But there are exemptions here, too, said Tisha Diffie, founder and CEO of After the Fact—Final Affairs, a company dedicated to helping families close estates.

"If a deceased person owed debt individually, even in a community property state, then only money from that person's estate can be used to pay back the debt," Diffie said.

5. Dealing with collection calls. If there are credit card debts, don't be surprised if you find yourself answering calls from collection agencies.

There are three things you need to determine: First, is the debt valid? Second, is it within the statute of limitations (typically four to six months after a death notice has been published)? Third, is it your responsibility?

While credit card companies and collection agencies might not lie and tell you that you are required to repay the debt when you are not, they may "imply that there's a moral obligation," said Detweiler of Credit.com.

Certainly, if you feel obligated, then pay the debt back, Detweiler said.

But there's no legal imperative to do so. If creditors are being aggressive, calling frequently and misrepresenting your responsibility, tell them to stop and then immediately follow up with a letter. The Consumer Financial Protection Bureau has sample letters you can use. You may also submit a complaint through the bureau.

—By Ilana Polyak, special to CNBC.com