Massachusetts estate tax returns may be filed online through MassTaxConnect. You will need to create an online account to file the estate tax return.This guide covers how to file and pay your estate tax return; including how to calculate the maximum federal credit. This is a federal Form 1041 and a Form 2 for Massachusetts. Refer to Their Will. The worksheet will help you correctly determine the income to report on the decedent's final return and on the return for either the estate or a beneficiary. This tax will also apply to the entire estate value. I am looking for guidance on opening an estate account for a relative from MA who died several years ago. Here's what you need to know about the deceased's final tax return, reporting income and deductions, inheritance and more. Massachusetts inheritance tax is due on future interests on other trusts that fall in as a result of the decedent's death.