A defined benefit plan is a pension your own business promises to fund, and it supports the largest deductible retirement contributions in the tax code, routinely $100,000 to $300,000 or more per year for a high-earning owner. Instead of capping what goes in each year, the law caps the benefit that comes out at retirement, and an actuary works backward to compute the annual funding needed to deliver it. It fits self-employed owners, S corporation shareholders and small firms with high, consistent profits, especially owners over 45 with few or no employees.
How the actuarial math turns a benefit cap into a six-figure deduction
The plan promises a specific annual retirement benefit, up to the limit set by Section 415(b). An enrolled actuary then calculates each year's required contribution from the owner's age, compensation and the plan's target benefit. The older the owner and the shorter the runway to retirement, the larger the annual funding has to be, which is exactly why the deduction dwarfs a SEP-IRA or a solo 401(k) for owners in their 50s: a defined contribution plan caps the input, while a defined benefit plan funds toward an output.
Contributions are deductible to the business, but Section 412 makes minimum funding largely mandatory each year, and that obligation is the defining trade-off against discretionary plans like a SEP. The plan needs a formal document, an actuary who certifies funding annually on Schedule SB, and a Form 5500 series filing each year; a one-participant plan files Form 5500-EZ once assets exceed $250,000. Employees who meet the eligibility rules must be covered under the nondiscrimination tests, which is why the design works best when the owner is the oldest and highest-paid person in the business. The modern version is almost always a cash balance plan, which expresses the promised benefit as a hypothetical account balance with annual pay credits and interest credits: same legal machinery, much easier to explain and to roll over at termination. Since the SECURE Act, a plan can be adopted as late as the business's tax filing deadline, including extensions, and still count for the prior year.
2025 and 2026 figures
The Section 415(b) maximum annual benefit is $280,000 for 2025; the figure is indexed annually, so the 2026 amount will be at or above that, and the actuary uses the published limit for the plan year. The compensation that can be counted in the funding formula is capped at $350,000 for 2025, also indexed. For stacking purposes, the 2025 employee deferral limit for a 401(k) is $23,500 plus a $7,500 catch-up at age 50. Required contributions for a plan year are generally due by 8.5 months after the plan year ends, and missing the Section 412 minimum triggers a 10% excise tax on the shortfall under Section 4971. If you see a 2026 dollar amount quoted, confirm it against the IRS's annual cost-of-living announcement rather than assuming last year's number.
For creators and the self-employed
The plan is built for the creator or consultant whose business has matured into steady mid-six-figure profit: course revenue, retainers, brand partnerships that renew, an agency with predictable margin. For a sole proprietor, funding is keyed to net earnings from self-employment (Schedule C profit less half of self-employment tax), and the deduction lands as an adjustment on the Form 1040. For an S corporation owner, funding is keyed to W-2 wages, and the corporation deducts the contribution on Form 1120-S, which reduces the profit flowing through on the K-1. That wage linkage matters: a $50,000 salary cannot support $200,000 of pension funding, so the defined benefit conversation and the reasonable compensation conversation happen together, and owners often raise their salary in the adoption year.
The standard structure pairs the pension with a solo 401(k): the owner still makes the full employee deferral plus catch-up, and the business adds a profit sharing contribution that is generally limited to 6% of compensation when a defined benefit plan sits alongside it. Combined deductions past $300,000 in a year are realistic for an owner in her mid-50s. The commitment runs the other way too: the IRS expects a plan to be permanent, which in practice means being prepared to fund it for several years, so the fit test is income consistency, not just income size.
Mistakes that cost money
- Adopting on volatile income. Funding is mandatory, not optional. A creator whose revenue drops 60% the year after adoption still owes the minimum contribution, and a missed minimum triggers the 10% excise tax on top of the funding obligation.
- Keeping the S corporation salary too low. The benefit formula runs on W-2 compensation; a lean salary strangles both the deduction and the ultimate benefit, and retroactive fixes are limited.
- Hiring without redoing the math. Nondiscrimination testing typically requires meaningful contributions for eligible staff, often 5% to 7.5% of their pay in a cash balance design. Adding two employees without re-running the numbers can quietly turn the plan uneconomic.
- Treating it as a one-year deduction. Opening a plan for a single windfall year and terminating it immediately invites the IRS to argue the plan was never permanent, putting the deductions at risk.
- Blowing the filings. A late Form 5500-EZ accrues penalties per day; the IRS runs a fixed-fee late-filer relief program, but only if you use it before being contacted.
Winding down: termination and rollover
A defined benefit plan is meant to end deliberately. When the owner retires, sells the business, or income falls for good, the plan is formally terminated, benefits are settled, and the assets roll tax-free into an IRA or 401(k), where the money keeps compounding under ordinary distribution rules. The trap at the end is overfunding: assets above what the promised benefits require cannot simply be handed back, and a reversion to the employer can face an excise tax of up to 50%, so actuaries deliberately steer annual funding inside a range rather than to the theoretical maximum. Underfunding at termination must be topped up.
This is the one retirement plan you should never adopt from a generic template: have an actuary run a design study against two or three years of real profit before signing anything, and revisit the funding target every year with your tax preparer.