UPDATE: On March 24, the IRS ended its silence on the question whether the filing and payment postponement applies to gift tax returns. Its answer is “no”. [We guessed wrong!]
A taxpayer can extend the due date of a gift tax return for six months, by filing a Form 8892, even if the taxpayer relies on the filing and payment postponement for an income tax return. However, it is necessary to pay any gift tax due with the Form 8892.
In “postponing” the due date for the 2019 Form 1040, the IRS states that the postponement applies only to federal income taxes. However, the 2019-gift tax return instructions provide that “Any extension of time granted for filing your calendar year 2019 federal income tax return will also automatically extend the time to file your 2019 federal gift tax return.”
An extension applies to one taxpayer; the “postponement” applies to all taxpayers. While they are technically different, they have the same practical effect.
Our best guess is that the IRS will treat a 2019 gift tax return the same way it treats a 2019 income tax return. It will treat both as due on July 15, 2020.