Situs

The location where a trust or other entity is based and typically taxed is called the "situs" of that trust. Situs is not always the same as governing law. You might, for example, have a trust with a situs in State A, taxed in State A, but State X laws may apply. The tax situs of a trust is not often obvious, and there are significant differences in the rules between various states, and many are inconsistent so that planning traps and opportunities abound.