When managing an irrevocable non-grantor trust, the trustee essentially keeps two sets of books. One book is for the beneficiaries, determining what they get paid. The other is for the IRS, determining what taxes are owed. These two amounts are rarely the same.

This split exists because trusts operate under two different rulebooks. The first, which governs distributions to beneficiaries, is based on the trust document itself and state laws. The second, which governs taxes, is the federal tax code. Understanding this distinction is the key to fiduciary accounting.

Fiduciary Accounting Income, or FAI, is the amount of money available to be distributed to the income beneficiaries. Think of it as the trust's spendable cash flow for the year. The rules for calculating FAI are set first by the trust document. If the document is silent on a particular issue, the trustee looks to state law.

Most states have adopted a version of the Uniform Principal and Income Act (UPIA). This act provides a default set of rules that distinguishes between two types of money a trust can receive: income and principal.

Imagine a trust that owns an apple orchard. The apples harvested each year are the income. The orchard itself—the land and the trees—is the principal. If the trustee sells some apples, the cash received is FAI. If the trustee sells five acres of the land, that cash is an addition to principal, not income.

The creator of the trust can change these default rules. For example, a trust document could state that capital gains are to be treated as income. This gives grantors flexibility to achieve specific goals. But in the absence of such instructions, the trustee must follow the state's UPIA rules.

Taxable income is a different concept entirely. It's whatever the Internal Revenue Code (IRC) says is taxable. The IRC’s definition is often broader than FAI and doesn't care about the distinction between income and principal in the same way.

For a trust, taxable income includes almost everything: dividends, interest, rent, and capital gains. This is where the confusion often begins. Just because a beneficiary isn't entitled to receive the money from a capital gain doesn't mean the IRS ignores it.

Let's use an example. The Evergreen Trust has the following activity for the year:

• Receives $15,000 in stock dividends.
• Sells a stock holding, realizing a $100,000 capital gain.

The trust document is silent on capital gains, so the default UPIA rules apply.

Here’s the breakdown:

1. Fiduciary Accounting Income: Only the $15,000 in dividends is considered income. The $100,000 capital gain is an addition to principal. So, the beneficiary is entitled to a distribution of $15,000.

2. Taxable Income: The IRS sees the whole picture. The trust's total taxable income is $115,000 ($15,000 dividends + $100,000 gain).

3. Who Pays the Tax: The beneficiary receives the $15,000 in income, so they are responsible for the tax on that amount. The trust retains the $100,000 capital gain, so the trust itself must file a tax return and pay the taxes on that gain.

This separation ensures that the long-term value of the trust (the principal) is preserved for future beneficiaries, while the current income beneficiaries receive the earnings. The trustee’s job is to navigate both sets of rules correctly, ensuring beneficiaries get what they are owed and the IRS gets what it is due.