(a) A company may not conduct a trust business in this state unless the company is a trust institution and is:
(1) a state trust company chartered pursuant to this subtitle;
(2) a bank, savings association, savings bank, or credit union that maintains its principal office or a branch in this state in accordance with governing law, or another office in this state with the power to conduct a trust business to the extent permitted by rule;
(3) a trust company chartered under the laws of another state or a foreign country that has a trust office in this state licensed by the banking commissioner pursuant to this chapter; or
(4) a foreign bank with an office in this state that is authorized to act as a fiduciary pursuant to Section 204.106.
(b) Notwithstanding Subsection (a), a trust institution that does not maintain a principal office, branch, or trust office in this state may act as a fiduciary in this state to the extent permitted by Subchapter A, Chapter 505, Estates Code.

(c) A company does not engage in the trust business in this state in a manner requiring a charter or license under this subtitle by engaging in an activity identified in Section 182.021, except that the registration requirements of Section 187.202 may apply to a trust representative office engaging in the activity.