A common trust fund is a pooled investment vehicle that a bank or trust company creates to combine assets from the trust accounts, estates, and guardianships it manages as fiduciary. Rather than investing each account separately, the bank runs one fund in which every participating account owns a proportionate share of the holdings and receives a proportionate share of income, gains, and losses. The vehicle qualifies for pass-through tax treatment under Internal Revenue Code Section 584 and is exempt from the securities registration rules that apply to mutual funds. Regulators now call these vehicles “collective investment funds,” though the tax code still uses the older name.
Who Can Actually Use One
You cannot buy into a common trust fund the way you would a mutual fund. Money reaches the fund only through a fiduciary relationship with the sponsoring bank, and only if the governing trust document or court order does not prohibit commingling assets with other accounts. That access limit is baked into the law.
Common trust funds are excluded from the definition of “investment company” under the Investment Company Act of 1940. That exclusion depends on three conditions: the fund must be used solely to help the bank administer trusts and estates, interests in the fund cannot be advertised or offered to the general public beyond ordinary marketing of the bank’s fiduciary services, and fees cannot violate fiduciary principles under federal or state law.1Office of the Law Revision Counsel. 15 U.S. Code 80a-3 – Definition of Investment Company Because the fund never reaches the public market, it avoids SEC registration, prospectus delivery, and the ongoing reporting mutual funds face. Fees tend to run lower than comparable mutual fund strategies as a result.
How the Fund Is Structured and Governed
For national banks, the Office of the Comptroller of the Currency governs these funds through 12 CFR 9.18. That regulation covers every operational requirement, from the fund’s written governing plan to how often assets must be valued.2eCFR. 12 CFR 9.18 – Collective Investment Funds State-chartered banks follow parallel rules from their state banking regulators, and the structure is largely the same.
The bank must keep fund assets strictly separated from its own balance sheet. Participating interests belong to the trust accounts, not to the bank. If the bank becomes insolvent, its creditors cannot reach the fund’s assets to satisfy the bank’s debts.3Office of the Comptroller of the Currency. OCC Comptroller’s Handbook – Collective Investment Funds
One point that catches people off guard: assets in a common trust fund are not insured by the FDIC. The fund holds investment securities, not bank deposits, so deposit insurance does not apply.3Office of the Comptroller of the Currency. OCC Comptroller’s Handbook – Collective Investment Funds The value of your participation rises and falls with the market.
Moving Money In and Out
Before a trust account enters the fund, the fiduciary must confirm that the trust instrument does not prohibit commingling. Once cleared, the account is assigned units of participation based on the value of the assets contributed, measured at the fund’s next valuation date.
A bank can accept in-kind contributions, meaning the trust transfers existing securities into the fund rather than selling them first and contributing cash. That avoids triggering capital gains from a sale on the open market. The mechanic runs in reverse on the way out: a withdrawing account can receive a proportionate share of the fund’s underlying securities instead of cash.
Withdrawal rules are tighter than most people expect. The bank must approve a withdrawal request on or before the valuation date used to calculate the exit price. Once that valuation date passes, the request cannot be canceled. For funds invested primarily in real estate or other illiquid assets, the bank can require up to one year of advance notice before a withdrawal.2eCFR. 12 CFR 9.18 – Collective Investment Funds You cannot liquidate a building overnight to pay out a departing account, and the rule reflects that.
Valuation and Unit Pricing
Under 12 CFR 9.18, the bank must value readily marketable assets like publicly traded stocks and bonds at least once every three months. Assets that are not readily marketable, such as real estate or private placements, must be valued at least once a year.2eCFR. 12 CFR 9.18 – Collective Investment Funds Many banks price liquid funds more frequently, and some run daily valuations for operational convenience, but quarterly is the legal baseline.
The unit price works like a mutual fund’s net asset value: total market value of the fund’s assets, minus liabilities, divided by the number of outstanding units. Accounts enter and exit at the unit price determined on the relevant valuation date, which prevents existing participants from being diluted by new entrants or disadvantaged by departing accounts.
Audits and Account Reporting
The bank must arrange an independent audit of each common trust fund at least once every twelve months, conducted by auditors who report solely to the bank’s board of directors.2eCFR. 12 CFR 9.18 – Collective Investment Funds From that audit, the bank prepares an annual financial report that must include:
- Every investment in the fund, showing both cost and current market value
- A summary of purchases, sales with profit or loss, and other investment changes since the previous report
- All cash income and disbursements during the period
- Any investments in default
The bank sends this report, or a notice that a free copy is available, to every account holder who would normally receive periodic trust accountings. The report cannot include predictions or representations about future performance.2eCFR. 12 CFR 9.18 – Collective Investment Funds Historical returns are allowed; forecasts are not.
How Taxes Work
The fund itself pays no federal income tax. Section 584 provides that a common trust fund “shall not be subject to taxation under this chapter and for purposes of this chapter shall not be considered a corporation.”4Office of the Law Revision Counsel. 26 U.S. Code 584 – Common Trust Funds Everything flows through to the participating accounts.
Each participating trust or estate picks up its proportionate share of three categories: short-term capital gains and losses, long-term capital gains and losses, and ordinary taxable income.4Office of the Law Revision Counsel. 26 U.S. Code 584 – Common Trust Funds Character is preserved as income passes through, so qualified dividends received by the fund keep their favorable rate when they reach the participating trust.
Reporting runs in two steps. The common trust fund files a return allocating income to each participating account. The participating trust or estate then reports that income on IRS Form 1041 and determines how much is distributable to beneficiaries. Final beneficiaries receive a Schedule K-1 from the trust, not from the common trust fund directly.5Internal Revenue Service. About Form 1041, U.S. Income Tax Return for Estates and Trusts Each beneficiary then reports the income on a personal return. From the beneficiary’s perspective, the trust simply produced investment income.
One practical consequence of the pass-through design deserves attention. A participating trust must include its share of the fund’s income whether or not the fund actually distributed any cash during the year. If the fund reinvests all gains, the trust still owes tax on its allocated share.4Office of the Law Revision Counsel. 26 U.S. Code 584 – Common Trust Funds Fiduciaries managing smaller trusts sometimes overlook this, and a strong year with no distributions can produce an unexpected tax bill.