Not every Trustee will automatically be required to provide an accounting of trust assets, but it is prudent practice for all Trustees to maintain documentation as if they will be required to prepare an accounting for the beneficiaries. Vested beneficiaries are legally entitled to receive a full accounting if they make such a request to the Trustee. At a minimum, most beneficiaries want an informal accounting with bank statements to confirm they are receiving a full distribution from the trust. If you believe you are a beneficiary of a trust, and your interest has vested, which often only occurs once the testator has passed away, it is advisable that you make a formal request for a copy of the trust document, an inventory of trust assets, as well as an accounting. The request should be in writing and should be mailed, via certified mail with tracking, to the Trustee and/or attorney for the Trustee. Putting the request in writing and having proof that the letter was received by the Trustee will be beneficial for evidentiary purposes if you have to petition the court.