I am winding up her affairs and wish to park a substantial sum in a savings account at the bank where the revocable (now irrevacable) living trust has an account. The bank is insisting on a tax ID (not SSN) for the now irrevacable living trust. She passed away within the last 6 weeks and I am uncertain when her affairs will be settled - not more than 6 months I hope. If I wish to earn interest on the cash proceeds of her estate I need a tax ID. The only question on the table is the election to count the interest as a part of her estate. I am Mother's personal representative and a trustee. Guess I need to read Pub 559 to fugure out the difference between making the 645 election and not making the election.