Generally, if a trust is the beneficiary of a retirement account, the retirement account is treated as not having a designated beneficiary. When a retirement account does not have a designated beneficiary, the distribution options for the beneficiary are more restrictive. There is an exception to this rule for a trust beneficiary, if the trust is a qualified trust. Under this exception, a qualified trust has the same distribution options as those which would apply to the oldest beneficiary of the trust had that person been named as the direct beneficiary of the retirement account.
In order for trust to be qualified, it must meet certain requirements. One of those requirements is that certain documentation must be provided to the IRA custodian or plan trustee by October 31 of the year that follows the year in which the retirement account owner died.
For more on what defines a trust as a qualified trust, including the documentation which must be provided to the custodian/trustee, see https://iradictionary.com/definitions/qualifiedtrust
