Answer:
Take a look at the instructions on IRS Form W-9. For a true trust, the IRS wants the depositor to supply the TIN of the trust.
It's only for a revocable "donor" trust that the IRS wants the SSN of the donor. Once that trust is made irrevocable (by action of the donor or by death of same), trust tax returns have to be filed, and a need for an EIN develops.
First published on BankersOnline.com 8/12/02