Title 26 › Subtitle Subtitle A— Income Taxes › Chapter 1— NORMAL TAXES AND SURTAXES › Subchapter D— Deferred Compensation, Etc. › Part III— RULES RELATING TO MINIMUM FUNDING STANDARDS AND BENEFIT LIMITATIONS › Subpart A— Minimum Funding Standards for Pension Plans › § 433
CSEC plans are pension plans run by groups of cooperatives and charities, and they follow their own funding rules to make sure enough money is set aside to pay promised benefits. Each plan keeps a "funding standard account." Every year the account is charged with the plan's normal cost plus installment payments that pay down shortfalls over set periods: costs added by plan amendments over 15 years, experience losses over 5 years, and losses from changed actuarial assumptions over 10 years. Employer contributions, and gains amortized over matching periods, are credited back. If total charges ever exceed total credits, the plan has an "accumulated funding deficiency." Shortfalls of older plans were spread over 40 years (plans existing on January 1, 1974) or 30 years (plans created after that but before the first plan year beginning after December 31, 2013), and payoff schedules in effect before 2014 stay in place until finished. An actuary must value the plan at least once a year using assumptions that are reasonable and reflect the plan's real experience. Assets are valued by a reasonable method that takes fair market value into account. Contributions made up to 8½ months after the close of a plan year still count for that year. Changing the plan's funding method or plan year requires government approval, and the government can stretch a payoff schedule by up to 10 years if that is needed to keep the plan going or to avoid big cuts in benefits or pay. The interest rate used to measure the plan's current liability is the third segment rate used for other pension funding rules, and certain plans may also keep a simpler "alternative minimum funding standard account." A plan that was less than 100 percent funded for the prior year must pay in four quarterly installments, due April 15, July 15, October 15, and January 15 of the following year. Each installment is 25 percent of the required annual payment, which is the lesser of 90 percent of the amount required for this year or 100 percent of the amount required for last year. Late or short installments are charged interest at the greater of 175 percent of the federal mid-term rate or the plan's own interest rate, and a plan low on cash can be treated as missing an installment if it does not pay enough in liquid assets. If unpaid required payments plus interest climb above $1,000,000 while the plan is underfunded, the unpaid amount is treated like taxes owed to the United States, with a lien that the Pension Benefit Guaranty Corporation can enforce. The employer must notify that agency within 10 days of the missed due date. If the plan's funded percentage falls below 80 percent at the start of a plan year, the plan is in "funding restoration status." The plan's actuary must certify the plan's status by the 90th day of each plan year. Once a plan is certified as being in that status, the sponsor has 180 days to adopt a written funding restoration plan designed to bring funding back to 100 percent within 7 years or the shortest practical time, whichever is longer. While in that status, amendments that raise benefits are blocked unless required by law or unless the sponsor pays the full added cost as an extra contribution. A few side rules round things out. When someone joins the plan already holding years of past service, only part of that earlier service counts toward the plan's current liability at first: 20 percent after 1 year of participation, rising in steps to 100 percent at 5 or more years (the employer can elect out of this rule). Benefits that depend on unpredictable events do not count as liabilities until the event happens. And a plan can never be forced to fund above its "full funding limitation," which is roughly its accrued liability minus its assets, but no less than 90 percent of current liability minus assets.
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Internal Revenue Code — Source: USLM XML via OLRC
Legislative History
Reference
Citation
26 U.S.C. § 433
Title 26 — Internal Revenue Code
Last Updated
Apr 6, 2026
Release point: 119-73