There are some states that still levy an estate tax and can be expensive places to pass away, according to Forbes in "Where Not To Die in 2018."
Some states tie their exemption level to the federal government's, such as Hawaii and Maine. Those states get an automatic tax break.
Some other states have already passed legislation to do the same thing and other states have recently repealed their estate taxes.
Oregon and Massachusetts are tied for the lowest estate tax exemptions in the country at $1 million. Oregon's system is complex and depends on what type of property the estate holds and who the heirs are. Massachusetts has a much stricter system.
As more and more states do away with their estate taxes, pressure is mounting on those remaining states that still have their own estate taxes. The pressure is either to scrap the taxes or at least to raise the exemptions.
Reference: Forbes (Dec. 21, 2017) "Where Not To Die in 2018."