(a) The venue of an action under Section 115.001 of this Act is determined according to this section.
(b) If there is a single, noncorporate trustee, an action shall be brought in the county in which:
(1) the trustee resides or has resided at any time during the four-year period preceding the date the action is filed; or
(2) the situs of administration of the trust is maintained or has been maintained at any time during the four-year period preceding the date the action is filed.

(b-1) If there are multiple trustees none of whom is a corporate trustee and the trustees maintain a principal office in this state, an action shall be brought in the county in which:
(1) the situs of administration of the trust is maintained or has been maintained at any time during the four-year period preceding the date the action is filed; or
(2) the trustees maintain the principal office.
(b-2) If there are multiple trustees none of whom is a corporate trustee and the trustees do not maintain a principal office in this state, an action shall be brought in the county in which:
(1) the situs of administration of the trust is maintained or has been maintained at any time during the four-year period preceding the date the action is filed; or
(2) any trustee resides or has resided at any time during the four-year period preceding the date the action is filed.
(c) If there are one or more corporate trustees, an action shall be brought in the county in which:
(1) the situs of administration of the trust is maintained or has been maintained at any time during the four-year period preceding the date the action is filed; or
(2) any corporate trustee maintains its principal office in this state.
(c-1) Notwithstanding Subsections (b), (b-1), (b-2), and (c), if the settlor is deceased and an administration of the settlor’s estate is pending in this state, an action involving the interpretation and administration of an inter vivos trust created by the settlor or a testamentary trust created by the settlor’s will may be brought:
(1) in a county in which venue is proper under Subsection (b), (b-1), (b-2), or (c); or
(2) in the county in which the administration of the settlor’s estate is pending.
(d) For just and reasonable cause, including the location of the records and the convenience of the parties and witnesses, the court may transfer an action from a county of proper venue under this section to another county of proper venue:
(1) on motion of a defendant or joined party, filed concurrently with or before the filing of the answer or other initial responsive pleading, and served in accordance with law; or
(2) on motion of an intervening party, filed not later than the 20th day after the court signs the order allowing the intervention, and served in accordance with law.
(e) Notwithstanding any other provision of this section, on agreement by all parties the court may transfer an action from a county of proper venue under this section to any other county.
(f) For the purposes of this section:
(1) “Corporate trustee” means an entity organized as a financial institution or a corporation with the authority to act in a fiduciary capacity.
(2) “Principal office” means:
(A) if there are one or more corporate trustees, an office of a corporate trustee in this state where the decision makers for the corporate trustee within this state conduct the daily affairs of the corporate trustee; or
(B) if there are multiple trustees, none of which is a corporate trustee, an office in this state that is not maintained within the personal residence of any trustee, and in which one or more trustees conducts the daily affairs of the trustees.
(2-a) The mere presence of an agent or representative of a trustee does not establish a principal office as defined by Subdivision (2). The principal office of a corporate trustee or the principal office maintained by multiple noncorporate trustees may also be but is not necessarily the same as the situs of administration of the trust.
(3) “Situs of administration” means the location in this state where the trustee maintains the office that is primarily responsible for dealing with the settlor and beneficiaries of the trust. The situs of administration may also be but is not necessarily the same as the principal office of a corporate trustee or the principal office maintained by multiple noncorporate trustees.