A co-trustee is one of two or more people appointed to manage a trust together, with equal authority over the trust’s assets and administration unless the trust document says otherwise. Each co-trustee owes the same fiduciary duties a sole trustee would owe, and each carries personal legal exposure not only for their own decisions but, in some circumstances, for what the other trustee does. Most states follow the Uniform Trust Code, which sets the default rules for how co-trustees share power, make decisions, and handle disagreements.
Why a Trust Has More Than One Trustee
Grantors appoint co-trustees for practical reasons. Pairing a family member who understands the grantor’s values with a professional who understands investments is common. So is naming siblings together to keep the peace among adult children who would otherwise feel shut out. Some grantors simply want deliberation built in, so no single person can act on impulse. Whatever the reason, the structure creates built-in checks and shared accountability, both of which have consequences for the people serving.
The Duties You Take On
Fiduciary duties run to the beneficiaries. Not to each other, not to the grantor. Four duties define the role.
Loyalty
Every co-trustee must manage the trust solely for the benefit of its beneficiaries. Self-dealing is the clearest violation: a co-trustee cannot buy trust property for themselves, steer trust investments toward a business they own, or take a personal loan from the trust. Under the Uniform Trust Code’s loyalty provision, any transaction where a trustee’s personal interests conflict with their fiduciary role is presumptively voidable. The presumption reaches deals involving the trustee’s spouse, close relatives, or business associates. A beneficiary does not need to prove harm. The conflict alone unwinds the transaction unless the trust specifically authorized it or a court approved it in advance.
Prudence
Co-trustees must manage trust assets the way a reasonably careful person would, taking into account the trust’s purposes and the beneficiaries’ needs. That means thoughtful investment decisions, diversification, and not gambling with assets the beneficiaries depend on. The standard is objective, and it rises with expertise. A co-trustee who is a professional financial advisor will be judged against what their training implies, not what a layperson could manage.
Impartiality
When a trust has more than one beneficiary, co-trustees must treat them equitably. Equitably is not the same as equally. If the trust directs income to one beneficiary during their lifetime and principal to another afterward, the co-trustees must balance those competing interests rather than favor one. The trust’s own terms define what fair looks like, and systematically tilting toward one beneficiary over another is a breach.
Informing and Reporting
Co-trustees share an obligation to keep beneficiaries reasonably informed. Under the Uniform Trust Code framework adopted in most states, trustees must send at least annual reports to current beneficiaries showing trust property, liabilities, income, expenses, and the trustee’s compensation. Beneficiaries also have the right to request a copy of the trust document. Stonewalling an information request or skipping an accounting can trigger court-ordered remedies, including removal.
How Co-Trustees Make Decisions
The trust document controls. Some trusts require unanimous agreement for everything. Others set up majority rule, or hand one co-trustee final authority over a specific category like investments. When the document is silent, state law fills the gap.
The Uniform Trust Code’s default rule is majority action, not unanimous consent. Two out of three co-trustees can act over the third’s objection. With only two co-trustees, majority rule effectively collapses into unanimity, which is where deadlocks become a real risk. Some states keep unanimous consent as the default, so the governing rule depends on where the trust is administered.
Every co-trustee has an obligation to participate. Going passive and letting the other handle everything is not an option. The exceptions are genuine unavailability from illness, temporary incapacity, or a proper delegation. When a co-trustee is unavailable and the trust needs immediate action to prevent harm, the remaining co-trustees can act without waiting.
When You Can Be Liable for What Your Co-Trustee Does
This is the uncomfortable part of the role. A co-trustee can face personal liability for a breach of trust, and that liability sometimes reaches the other trustee’s conduct.
The general rule is that a co-trustee who did not participate in a particular decision is not liable for it. The protection vanishes if the co-trustee failed to exercise reasonable care to prevent a serious breach, or failed to pursue a remedy after learning of one. You cannot ignore red flags. If your co-trustee is making questionable investments, draining accounts, or refusing required distributions, staying quiet makes you liable too.
The obligation is specifically to prevent serious breaches and to compel the other co-trustee to fix them. A difference of opinion about investment strategy will not create liability. Looting the trust or self-dealing will, and the non-participating co-trustee has an affirmative duty to act, whether by objecting formally, demanding an accounting, or petitioning the court.
Protection If You Dissent
A co-trustee who disagrees with a majority decision but is outvoted has a specific protection. If they formally notify the other co-trustees of their dissent at or before the time of the action, they are generally not liable for that action. The exception is when the action is itself a serious breach of trust. In that case, dissenting is not enough. The dissenting co-trustee must take affirmative steps to prevent the breach or seek court intervention.
Getting Paid
Co-trustees are entitled to compensation, but serving together does not mean each one collects a full trustee’s fee. Most trust instruments specify what the trustee will be paid. When the document is silent, the standard in nearly every state is reasonable compensation under the circumstances. A court can adjust that amount in either direction if the trustee’s actual duties turn out to be substantially different from what was contemplated, or if the specified compensation is unreasonably high or low.
What counts as reasonable depends on the size and complexity of the trust, the skill the trustee brings, the time spent, the results achieved, and what other trustees in the community charge for similar work. When co-trustees serve together, the total paid to all of them generally cannot exceed what a single trustee would earn for the same work. The co-trustees then divide that amount based on their respective contributions. A co-trustee who handles day-to-day administration typically receives a larger share than one whose role is limited to reviewing quarterly statements.
Tax Responsibilities
Co-trustees share responsibility for the trust’s tax compliance, and mistakes here carry personal consequences.
Most trusts need their own Employer Identification Number. When applying, the trust must name a responsible party, defined as someone who owns, controls, or exercises effective control over the entity and directly or indirectly manages its funds and assets. The responsible party must be an individual. One co-trustee is listed on the application, but that does not shift the underlying tax obligations away from the others.1Internal Revenue Service. Responsible Parties and Nominees
A trust with gross income of $600 or more, any taxable income, or a nonresident alien beneficiary must file Form 1041, the U.S. Income Tax Return for Estates and Trusts. The IRS requires that the fiduciary, or one of the joint fiduciaries, file the return. Co-trustees need to agree on who handles preparation and filing, but all remain responsible for accuracy. Late or missing returns can produce penalties the co-trustees bear personally.2Internal Revenue Service. Instructions for Form 1041 and Schedules A, B, G, J, and K-1 (2025)
Co-trustees can also face personal liability for failing to honor an IRS levy served on the trust. If the IRS issues a levy related to a beneficiary’s tax debt and the trustee distributes assets to that beneficiary instead of honoring the levy, the trustee can be held personally liable for the amount that should have been surrendered.
Breaking a Deadlock
Two co-trustees who cannot agree on a distribution, investment, or sale can freeze the trust’s administration entirely. The trust document is the first place to look. Well-drafted trusts often include a tie-breaking procedure, such as a third party who casts the deciding vote or a mediation requirement before anyone goes to court.
If the document is silent, mediation with a neutral third party is usually the most practical next step. It costs a fraction of litigation and keeps the disagreement private. Many disputes between co-trustees stem from communication breakdowns or different risk tolerances rather than bad faith, and a skilled mediator can often bridge the gap.
When negotiation and mediation fail, a co-trustee or beneficiary can petition the court for instructions. The court can interpret ambiguous language, order a specific course of action, or restructure the trusteeship. Courts treat this as a last resort, and the legal fees come out of the trust, which means the beneficiaries bear the cost of the co-trustees’ inability to work together.
Resigning, Being Removed, and Vacancies
Stepping Down
A co-trustee who wants to resign must follow the process in the trust document. When the document is silent, the Uniform Trust Code generally allows resignation after at least 30 days’ written notice to the beneficiaries, the grantor (if living), and any other co-trustees. A court can approve a resignation on shorter notice. Resigning does not wipe the slate clean. Liability for acts or omissions that occurred before the resignation survives, and a resignation timed to enable another co-trustee’s breach can itself be treated as a breach of duty.
Involuntary Removal
Removing a co-trustee against their will requires a court order. A beneficiary or fellow co-trustee petitions the court, which grants removal only for serious cause. Common grounds include a significant breach of trust, a persistent failure to administer the trust effectively, lack of cooperation that substantially impairs administration, or unfitness due to incapacity. The court’s concern is what serves the beneficiaries’ interests, not punishing the trustee.
When One Co-Trustee Is Gone
When a co-trustee resigns, is removed, or dies, the remaining co-trustee can generally keep administering the trust without interruption. Under the Uniform Trust Code, a vacancy in a co-trusteeship does not need to be filled as long as at least one trustee remains in office. If no trustees remain, the vacancy must be filled through the succession process in the trust document. If the trust names no successor and the remaining parties cannot agree, the court will appoint one.