Mass. Gen. Laws ch. 203E § 702
In the case of a testamentary trust, a trustee shall furnish a bond for the performance of the trustee's fiduciary duties and a surety shall be required unless waived by the terms of the trust or found by the probate and family court department of the trial court to be not necessary to protect the interests of the beneficiaries. On petition of the trustee or other interested person the probate court may excuse a requirement of bond, reduce the amount of the bond, release the surety or permit the substitution of another bond with the same or different sureties. If the instrument creating the trust exempts the trustee from furnishing a bond or limits the amount thereof, or the probate court determines that the bond is insufficient, the probate court may, if it concludes that a bond is necessary or that a bond of a larger amount is necessary, require the furnishing of such bond. The terms and conditions of the bond shall be as set forth in section 3-606 of chapter 190B.
Mass. Gen. Laws ch. 203E, § 702