This is a recurring scene on the Bogleheads forum and personal finance corners of Reddit: high-savings households assume that being well under the federal threshold means they are done planning. In states with their own estate or inheritance tax (Massachusetts, Oregon, Washington, New York, Illinois, Maryland, and a handful of others), that assumption can cost six figures.If they live in Massachusetts and both pass away with the estate as it stands today, their heirs face a six-figure Massachusetts estate t ...