The IRA will have to be probated through the pour-over will and then distributed to the beneficiaries according to the terms of the trust. The tough thing will be to keep these classified as inherited IRAs for tax purposes.
Without a beneficiary, the proceeds will go into the estate and then pass according to the will (which may be a "pour-over" will into his trust.
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I agree with my colleagues. However, you might be able to access the IRA funds through a small estate affidavit, depending on the amount in the account. This is a quicker and less involved procedure than a full probate. You also want to check with the IRA fund to see if it will accept an affidavit as some funds will not.
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