Is the executor required to reveal his Social Security number when liquidating estate holdings?

No, they should not be required to provide their SSN. Estate holdings should be liquidated using the Estate's tax number. If there isn't one, then the executor is slipping up. Worst case would be to use the SSN of the deceased. Transactions have to be associated with a tax number. * The executor/executrix/administrator of the estate (whatever the title) is required to supply his or her SSN as well as that of the deceased or the TID when making a claim for the deceased estate with an insurance company and other such matters.