ERISA Section 302: Funding Rules, Waivers, and Excise Taxes

ERISA Section 302 is the provision of the Employee Retirement Income Security Act that requires employers sponsoring defined benefit pension plans to meet a minimum funding standard every plan year. Codified at 29 U.S.C. § 1082, it sets the annual contribution floor for single-employer defined benefit plans, money purchase plans, multiemployer (Taft-Hartley) plans, and cooperative and small employer charity (CSEC) plans, with different mechanics for each category.¹ Miss a contribution and the consequences move quickly: excise taxes, a statutory lien on the employer’s assets, and joint liability across every company in the controlled group.

What Section 302 Actually Requires

Since the Pension Protection Act of 2006 rewrote the funding rules for plan years beginning after 2007, Section 302 has functioned as a gateway. It states the requirement that every covered plan satisfy a minimum funding standard, then routes the actual calculation to a companion section based on plan type: Section 303 (29 U.S.C. § 1083) for single-employer defined benefit plans, Section 304 (29 U.S.C. § 1084) for multiemployer plans, and Section 305a (29 U.S.C. § 1085a) for CSEC plans.²

Section 302 has a near-identical counterpart in the tax code at IRC § 412, which conditions a plan’s tax-qualified status on meeting the same funding rules. ERISA § 302(a) mirrors IRC § 412(a); ERISA § 302(e) mirrors IRC § 412(m) on quarterly installments; and ERISA § 302(f) mirrors IRC § 412(n) on liens.³ A sponsor that underfunds a plan therefore faces exposure under both statutes.

How the Minimum Contribution Is Calculated for Single-Employer Plans

For single-employer defined benefit plans, Section 303 replaced the old funding standard account with a target-based approach. Every year the actuary compares plan assets to the “funding target,” which is the present value of all benefits participants have already earned.⁴

When assets fall short of the target, the minimum required contribution is the sum of three pieces:

The target normal cost: the present value of benefits expected to accrue during the current plan year, plus anticipated administrative expenses, minus mandatory employee contributions.
The shortfall amortization charge: installments that close the gap between assets and the funding target over seven years.
The waiver amortization charge: installments repaying any previously waived contributions over five years.

When assets equal or exceed the funding target, the obligation drops to the target normal cost reduced by the surplus. The contribution cannot go below zero.⁵

Discount Rates and Mortality Assumptions

The size of the funding target hinges on discount rates. Plans use three segment rates drawn from the corporate bond yield curve, matched to when benefits are expected to be paid: within five years, five to twenty years, and beyond twenty years. The IRS publishes updated 24-month average segment rates monthly.⁶

Congress has repeatedly narrowed the corridor around the 25-year averages of those rates. Under the American Rescue Plan Act of 2021 and the Infrastructure Investment and Jobs Act, segment rates for plan years 2020 through 2030 stay within a 95% to 105% band around the 25-year average. The corridor gradually widens back to 70% to 130% after 2034.⁶

At-Risk Status

Large, badly underfunded plans face tougher assumptions. A plan is “at-risk” if it has at least 500 participants, is less than 80% funded under normal assumptions, and is less than 70% funded when the actuary assumes every eligible participant retires at the earliest possible date and elects the most expensive benefit form. At-risk plans must use those conservative assumptions in their funding target, which raises the required contribution. If the plan has been at-risk in at least two of the preceding four years, an additional loading factor of $700 per participant plus 4% of the standard funding target applies.⁴

Quarterly Contributions and Liquidity

Sponsors of plans that had a funding shortfall in the prior year cannot wait until year-end. They owe quarterly installments during the current year. Each installment equals 25% of the “required annual payment,” defined as the lesser of 90% of the current year’s minimum required contribution or 100% of the prior year’s minimum.⁷

For a calendar-year plan, the installments fall on April 15, July 15, October 15, and January 15 of the following year. Late installments carry interest at the plan’s effective interest rate plus five percentage points.⁷

Sponsors subject to quarterly contributions must also maintain liquid assets sufficient to cover roughly three years of benefit payments. A liquidity shortfall forces additional contributions in liquid assets, is treated as a missed quarterly contribution, may trigger a 10% excise tax under IRC § 4971(f), and can bar the plan from paying lump sums and other accelerated forms.⁷

Multiemployer and CSEC Plans Follow Different Rules

Section 302 covers more than single-employer plans, and the mechanics diverge sharply once you leave that category.

Multiemployer (Taft-Hartley) plans still use a version of the pre-PPA funding standard account. Under ERISA § 304 and IRC § 431, the account is charged each year with normal cost and various amortization amounts and credited with employer contributions and favorable experience. The plan satisfies the standard if the account does not show an “accumulated funding deficiency” at year-end. Most amortizations run 15 years, including unfunded past-service liability for plans established on or after January 1, 2008, plan-amendment liability changes, experience gains and losses, and changes in actuarial assumptions.⁸

Multiemployer plans are also classified by “zone status” based on projected health. Plans in critical status (the red zone) under ERISA § 305 must adopt a rehabilitation plan; while a plan is in critical status and following that rehabilitation plan, contributing employers are exempt from Section 302’s standard joint and several liability for missed contributions.¹ The Multiemployer Pension Reform Act of 2014 added “critical and declining” status for plans projected to be insolvent within 15 years (or 20 in narrower cases), which can permit Treasury-approved benefit suspensions. Suspensions cannot reduce disability-based benefits, and participants aged 75 and older receive heightened protection.⁹

The American Rescue Plan Act of 2021 layered on additional relief. Its Special Financial Assistance program, administered by the PBGC, provides non-repayable lump-sum grants to eligible troubled multiemployer plans, sized to pay all benefits through the last plan year ending in 2051. Recipients are deemed to be in critical status through 2051, must segregate the funds and limit investments to investment-grade bonds or PBGC-approved assets, and face restrictions on benefit increases, contribution rate reductions, and withdrawal liability settlements. Plans that had previously suspended benefits under MPRA must reinstate them. ARPA also lets multiemployer plans spread COVID-19 investment and experience losses over 30 years and lets endangered or critical plans extend their improvement or rehabilitation periods by five years.¹⁰¹¹

Cooperative and Small Employer Charity plans are a separate track. Created by the CSEC Pension Flexibility Act of 2014, they cover defined benefit plans of rural cooperatives, plans of multiple 501(c)(3) charities, and plans of certain nationally chartered charities primarily serving children. These plans opted out of PPA and follow a modified pre-PPA framework under IRC § 433: liability changes from plan amendments amortize over 15 years, and there is no deficit reduction contribution. If the funded percentage drops below 80%, the plan enters “funding restoration status,” and the sponsor must adopt a plan to reach 100% funding within seven years, contribute at least normal cost annually, and generally forgo benefit increases unless additional contributions accompany them.¹²

When Sponsors Can Get a Waiver

The Secretary of the Treasury may waive the minimum funding standard when the employer faces genuine financial distress. For single-employer plans, the applicant must show “temporary substantial business hardship.” For multiemployer plans, the standard is met when at least 10% of contributing employers face “substantial business hardship.”²

The factors weighed include whether the employer is operating at an economic loss, whether unemployment in the relevant industry is substantial, whether industry profits are depressed or declining, and whether the plan can reasonably be expected to continue only if the waiver is granted. The Secretary must also find that denial would be adverse to participants’ interests as a whole.¹

Waivers are limited: no more than three in any 15 consecutive plan years for single-employer plans, and five out of 15 for multiemployer plans. Single-employer applications are due no later than the 15th day of the third month after the plan year ends. Before granting a waiver, the Secretary must consult with the PBGC through a 30-day notice-and-comment process, and may require the employer to post security. While a waiver is in effect, the plan generally cannot be amended to increase benefits or accelerate vesting.²

What Happens If a Sponsor Misses a Contribution

Section 302 makes the contributing employer primarily liable for required contributions. If the employer belongs to a controlled group under common ownership, every member of that group is jointly and severally liable. If the sponsor cannot pay, the IRS and PBGC can pursue any company in the corporate family for the full amount.¹

The $1 Million Statutory Lien

Section 302(f) creates a statutory lien that arises automatically when a single-employer plan sponsor misses required contributions and the total unpaid balance, including interest, exceeds $1 million. The lien attaches to all real and personal property of the contributing sponsor and every controlled-group member. The plan itself is the lienholder, but only the PBGC can perfect and enforce the lien, typically by filing notices in state recording offices.³

The $1 million threshold is measured by missed contributions plus interest, not by the plan’s accumulated funding deficiency. In practice, when the PBGC enforces the lien, it generally limits recovery to the plan’s actual funding deficiency.³

Once the threshold is crossed, the sponsor must notify the PBGC by filing Form 200 within 10 days of the missed payment’s due date. The form asks for the controlled-group structure, financial statements for the three most recent fiscal years, actuarial data, and the reason for the missed contribution. Failing to file can bring penalties under ERISA § 4071.¹³

Excise Taxes Under IRC § 4971

The Internal Revenue Code layers excise taxes on top of the lien. Under IRC § 4971(a), a 10% tax applies to the aggregate unpaid minimum required contributions remaining at year-end. If the employer does not correct the deficiency by the end of a defined “taxable period,” an additional 100% tax applies under IRC § 4971(b).¹⁴

“Correction” means contributing enough to bring the unpaid minimum required contribution to zero, with applicable interest. Contributions apply on a first-in, first-out basis to the earliest unpaid plan year. The Treasury Secretary can waive the 100% tax case by case. Terminating the plan is not an escape hatch: if an accumulated funding deficiency remains in the year of termination, the 100% penalty still applies.¹⁵

Who Enforces Section 302

Three federal actors share enforcement. The IRS administers the funding requirement through IRC § 412 and collects the § 4971 excise taxes. The Department of Labor’s Employee Benefits Security Administration administers the ERISA side. The PBGC monitors risks to plan solvency and holds the enforcement tools tied to missed contributions.¹⁶

PBGC oversight extends beyond individual missed payments. Under the Pension Protection Act, controlled groups with any plan funded below 80% must file annual financial and actuarial reports with the PBGC under ERISA § 4010.¹⁷ Through its Early Warning Program, the PBGC also tracks corporate transactions and bankruptcies that could threaten plan funding. If a plan fails to meet the minimum funding standard or will be unable to pay benefits when due, the PBGC can move to terminate it involuntarily.¹⁶

1
Cornell Law Institute. 29 U.S. Code § 1082 — Minimum Funding Standards
2
Office of the Law Revision Counsel. 29 U.S.C. § 1082 — Minimum Funding Standards
3
Pension Benefit Guaranty Corporation. PBGC Opinion Letter 633
4
Cornell Law Institute. 29 U.S. Code § 1083 — Minimum Funding Standards for Single-Employer Defined Benefit Pension Plans
5
Office of the Law Revision Counsel. 29 U.S.C. § 1083 — Minimum Funding Standards for Single-Employer Plans (2007 Edition)
6
Internal Revenue Service. Pension Plan Funding Segment Rates
7
U.S. Department of the Treasury. Quarterly Contribution Requirements for Single-Employer Plans
8
Office of the Law Revision Counsel. 26 U.S.C. § 431 — Minimum Funding Standards for Multiemployer Plans
9
Office of the Law Revision Counsel. 26 U.S.C. § 432 — Additional Funding Rules for Multiemployer Plans
10
Pension Benefit Guaranty Corporation. American Rescue Plan Act of 2021
11
Internal Revenue Service. IRS Notice 2021-57
12
Internal Revenue Service. IRS Notice 2015-58 — CSEC Pension Flexibility Act
13
Pension Benefit Guaranty Corporation. Form 200 Filing Instructions
14
Cornell Law Institute. 26 CFR § 54.4971(c)-1 — Taxes on Failure To Meet Minimum Funding Standards
15
Internal Revenue Service. Terminations of Underfunded Single-Employer Defined Benefit Plans
16
Pension Benefit Guaranty Corporation. Plan Funding FAQ
17
Federal Register. Annual Financial and Actuarial Information Reporting, Pension Protection Act of 2006