Whether you have to provide them a privacy notice depends. If you hold a custodial IRA, then the privacy notice applies. Simply being a trust customer does not make them a consumer.
From the regs:
An individual is not a bank's consumer solely because he or she has designated the bank as trustee for a trust.
(vii)
An individual is not a bank's consumer solely because he or she is a beneficiary of a trust for which the bank is a trustee.