The IRS does not currently have laws or rules regarding inheritance tax as of 2015, Nolo explains. Only six states impose an inheritance tax: Iowa, Kentucky, Maryland, Nebraska, New Jersey and Pennsylvania.
While there are no federal laws regarding inheritance tax, the federal government does impose an estate tax, according to the Internal Revenue Service. An inheritance tax is a tax imposed on items that a person inherits from an estate, while an estate tax is a tax imposed on the value of assets held in a deceased person's estate, according to About.com.
In all of the six states that impose an inheritance tax, property transferred to the surviving spouse is exempt from tax. In four of the six states, Kentucky, Maryland, New Jersey and Iowa, transfers to surviving children and grandchildren are exempt from inheritance tax. In Pennsylvania and Nebraska, assets that are transferred to surviving children and grandchildren or other collateral heirs, such as siblings, nieces or nephews, or friends, are subject to that state's inheritance tax.
In 2015, estates do not need to file an estate tax return unless the gross value of the estate is $5,430,000 or more, the IRS notes. This value rises every year.