You must complete the federal estate tax return (IRS Form 706) for the date of the decedent's death before filling out the Maryland estate tax return. There are two types of accounts, an interim account and a final account.With an interim account, not all estate assets are distributed. For decedents dying on or after October 1, 2023, a surviving registered domestic partner is exempt from inheritance tax. All filers must complete this part. An estate tax return in Maryland is a return that is due nine months from the date of death for both Maryland and the federal government. The beneficiary, and not the trust or decedent's estate, pays income tax on their distributive share of income. The Maryland estate tax return is due nine months from the date of a decedent's death.