Find common questions and answers about estate taxes, including requirements for filing, selling inherited property and taxable gifts. You will have to file all necessary tax forms and open a checking account in the name of the estate to pay any estate expenses.You must file Form ET-706 within nine months after the decedent's date of death, unless you receive an extension of time to file the return. New York State's estate tax is calculated using the tax table provided on Form ET706. There are multiple versions of Form ET-706.