Massachusetts General Laws Part II. Real and Personal Property and Domestic Relations (Ch. 183-210) Ch. 203E, § 813

(a) A trustee shall keep the qualified beneficiaries of the trust reasonably informed about the administration of the trust. Unless unreasonable under the circumstances, a trustee shall promptly respond to a qualified beneficiary's request for information related to the administration of the trust.

(b) Within 30 days after acceptance of the trust or the trust becomes irrevocable, whichever is later, the trustee shall inform, in writing, the qualified beneficiaries of the trustee's name and address. The information shall be delivered or sent by ordinary first class mail.

(c) A trustee shall send an account to the distributees and permissible distributees of trust income or principal and to other qualified beneficiaries who request it, at least annually and at the termination of the trust. The account of trust income and principal may be formal or informal, but shall include information relating to the trust property, liabilities, receipts and disbursements, including the amount of the trustee's compensation, a listing of the trust assets and, if feasible, their respective market values.

(d) A beneficiary may waive the right to a trustee's account of trust income or principal or other information otherwise required to be furnished under this section. A beneficiary, with respect to future accounts and other information, may withdraw a waiver previously given. A waiver of a trustee's account or other information shall not relieve the trustee from accountability and potential liability for matters that the account or other information would have disclosed.