A trust or corporate trust is an American English term for a large business with significant market power. It is often used in a historical sense to refer to monopolies or near-monopolies in the United States during the Second Industrial Revolution in the 19th century and early 20th century.

Trust Company can refer to:

• Trust company, a company acting as a trustee
• Trust Company (band)
• Trust Company, predecessor to SunTrust Banks

A trust company is a corporation, especially a commercial bank, organized to perform the fiduciary  of trusts and agencies. It is normally owned by one of three types of structures: an independent partnership, a bank, or a law firm, each of which specializes in being a trustee of various kinds of trusts and in managing estates. Trust companies are not required to exercise all of the powers that they are granted. Further, the fact that a trust company in one jurisdiction does not perform all of the trust company duties in another jurisdiction is irrelevant and does not have any bearing on whether either company is truly a "trust company". Therefore, it is safe to say that the term "trust company" must not be narrowly construed.