Cash Balance Plan Tax Deduction: Limits, Timing, and Funding

Employer contributions to a cash balance plan are deductible as an ordinary business expense, and the deductible amount is set by an enrolled actuary rather than by a fixed percentage of payroll. That is why the cash balance plan tax deduction can reach $200,000 to $300,000 or more per year for an owner in their 50s or 60s, and why it stacks on top of what a 401(k) already allows. The size of the deduction depends on the participant’s age, compensation, and how the plan is designed.

How the Deduction Is Calculated

Contributions to a qualified cash balance plan are deductible under Internal Revenue Code Section 404 at the business entity level, whether the sponsor is a C-corporation, S-corporation, partnership, or sole proprietorship.¹ The contribution reduces the business’s taxable income for the year it is made or allocated. Employees owe no income tax on the amounts credited to their accounts until distribution.

The ceiling on the deduction sits in IRC Section 404(o), which governs single-employer defined benefit plans. An enrolled actuary runs the numbers each year and certifies them on Schedule SB of Form 5500.² Three pieces feed the calculation:

The funding target, meaning the present value of all benefits participants have earned to date.
The target normal cost, meaning the present value of benefits expected to accrue during the current plan year.
The cushion amount, equal to 50 percent of the funding target plus any anticipated increases tied to expected future compensation growth.

The maximum deductible contribution is the sum of those three, minus the current value of plan assets.³ If the minimum required contribution under IRC Section 430 is larger than that figure, the employer can deduct the minimum instead.

The formula generally leaves room above the required minimum. An owner having a high-income year can contribute more than required, creating a pre-funding balance inside the plan that can offset the required contribution in a leaner year later.

Contributing more than the deductible limit triggers a 10 percent excise tax on the nondeductible excess under IRC Section 4972.⁴ The excess is not lost. It carries forward and can be deducted in a later year when there is room under the limit, but the 10 percent penalty makes accurate actuarial numbers matter before writing the check.

The Section 415 Benefit Cap and Why Age Drives the Number

The deduction formula is generous, but the underlying benefit the plan can promise has a ceiling. IRC Section 415(b) caps the annual retirement benefit at the lesser of $290,000 (for 2026) or 100 percent of the participant’s average compensation during their three highest-paid consecutive years.⁵ That is the annual annuity payable at age 62 or later, so the lump-sum value at retirement can exceed $3 million for a long-tenured participant.

Age is what makes the deduction so much larger for older owners. A 60-year-old has only a few years to fund a benefit approaching the $290,000 annual cap, so the actuary compresses the required contributions into that shorter window. Annual deductible contributions for owners in their late 50s and 60s can exceed $250,000 or $300,000, while a 40-year-old at the same compensation might see a maximum closer to $100,000 to $150,000.

Stacking a Cash Balance Plan on Top of a 401(k)

Most owners who adopt a cash balance plan also run a 401(k) or other defined contribution plan. The two follow separate deduction rules, and the combined shelter is much larger than either alone.

For a standalone defined contribution plan, employer contributions are deductible up to 25 percent of the total compensation paid to participants. The cash balance deduction sits outside that 25 percent ceiling entirely and is limited only by the actuarial formula above.³ The employer deducts the full cash balance contribution, then separately deducts up to 25 percent of covered payroll on the defined contribution side.

The 6 Percent Gateway

When one business sponsors both a defined benefit plan and a defined contribution plan covering overlapping employees, IRC Section 404(a)(7) applies a combined deduction limit. That combined cap does not apply as long as employer contributions to the defined contribution plan stay at or below 6 percent of covered payroll.¹ Employee salary deferrals to the 401(k) do not count toward that 6 percent threshold.

Most combined designs keep employer profit-sharing and matching at or below 6 percent for exactly that reason. Below the line, each plan’s deduction is calculated independently. Above it, the combined limit can pull the total deduction below what the actuary calculated for the cash balance side alone.

When the Plan Has to Exist and When the Money Has to Be In

The plan itself does not have to be in place before year-end. A cash balance plan can be adopted by the due date for filing the employer’s tax return, including extensions, and still generate a deduction for that prior year. An unexpectedly profitable year can still be sheltered after the fact.

Contributions must be deposited into the plan trust by the tax return due date, including extensions, to count for the prior year.³ For most calendar-year businesses that file an extension, the outside deadline is September 15. When contributions are deposited after year-end, the employer should notify the plan trustee in writing that the deposit applies to the prior plan year.

What the Deduction Locks You Into

The deduction is available because the plan carries real obligations. Those obligations are worth understanding before adoption because they cannot be turned off in a bad year.

Minimum Funding Is Not Optional

Once the plan is adopted, the employer is legally required to make at least the minimum required contribution each year as calculated by the enrolled actuary under IRC Section 430. Missing or shorting that contribution triggers a first-tier excise tax equal to 10 percent of the total unpaid minimum required contributions at the end of the plan year, imposed under IRC Section 4971.⁶ The employer reports and pays it on Form 5330.⁷

If the shortfall is not corrected by the end of the taxable period, a second-tier excise tax of 100 percent of the remaining unpaid amount applies.⁶ Persistent underfunding can also cost the plan its qualified status, which would put every prior year’s deduction at risk. Funding waivers exist for severe business hardship but are rarely granted and require a showing that the waiver serves the plan participants’ best interest.

PBGC Premiums

A cash balance plan is a defined benefit pension, so it is covered by the Pension Benefit Guaranty Corporation, which charges annual premiums. For 2026, every single-employer plan owes a flat-rate premium of $111 per participant. If the plan has unfunded vested benefits, an additional variable-rate premium of $52 per $1,000 of underfunding applies, capped at $751 per participant.⁸ Premiums are themselves deductible, but they are fixed regardless of business profitability.

Top-Heavy Contributions for Staff

Cash balance plans adopted by small businesses with highly paid owners almost always qualify as top-heavy, meaning more than 60 percent of plan assets are attributable to key employees. Top-heavy status requires the employer to provide a minimum benefit to non-key participants generally equal to at least 3 percent of each employee’s total annual compensation.⁹

The owner’s deduction is not free of cost when the business has staff. Contributions for rank-and-file employees are deductible on the same terms, but they are real cash out the door and belong in the projection before the plan is adopted.

1
Internal Revenue Service. Combined Limits Under IRC Section 404(a)(7)
2
U.S. Department of Labor. Single-Employer Defined Benefit Plan Actuarial Information
3
Office of the Law Revision Counsel. 26 US Code 404 – Deduction for Contributions of an Employer to an Employees Trust or Annuity Plan and Compensation Under a Deferred-Payment Plan
4
Office of the Law Revision Counsel. 26 US Code 4972 – Tax on Nondeductible Contributions to Qualified Employer Plans
5
Internal Revenue Service. COLA Increases for Dollar Limitations on Benefits and Contributions
6
Office of the Law Revision Counsel. 26 US Code 4971 – Taxes on Failure to Meet Minimum Funding Standards
7
Internal Revenue Service. Form 5330 – Return of Excise Taxes Related to Employee Benefit Plans
8
Pension Benefit Guaranty Corporation. Comprehensive Premium Filing Instructions for 2026 Plan Years
9
Internal Revenue Service. Is My 401(k) Top-Heavy?