What is US Federal "Death Tax"?

The estate tax in the United States is a tax on the transfer of the estate of a deceased person. The tax applies to property that is transferred via a will or according to state laws of intestacy. Other transfers that are subject to the tax can include those made through an intestate estate or trust, or the payment of certain life insurance benefits or financial account sums to beneficiaries. The estate tax is one part of the Unified Gift and Estate Tax system in the United States. The other part of the system, the gift tax, applies to transfers of property during a person's life.

In addition to the federal estate tax, many states have enacted similar taxes. These taxes may be termed an "inheritance tax" to the extent the tax is payable by a person who inherits money or property of a person who has died, as opposed to an estate tax, which is a levy on the estate (money and property) of a person who has died. The tax is often the subject of political debate, and opponents of the estate tax call it the "death tax". Some supporters of the tax have called it the "Paris Hilton tax".

If an asset is left to a spouse or a federally recognized charity, the tax usually does not apply. In addition, a maximum amount, varying year by year, can be given by an individual, before and/or upon their death, without incurring federal gift or estate taxes: $5,340,000 for estates of persons dying in 2014 and 2015 $5,450,000 (effectively $10.90 million per married couple, assuming the deceased spouse did not leave assets to the surviving spouse) for estates of persons dying in 2016. Because of these exemptions, it is estimated that only the largest 0.2% of estates in the U.S. will pay the tax. For 2017, the exemption increased to $5.5 million. In 2018, the exemption doubled to $11.18 million per taxpayer due to the Tax Cuts and Jobs Act of 2017. As a result, only about 2,000 estates per year in the US are currently liable for estate tax.

Source - Wikipedia: Estate Tax in United States