11.3 Employer Plans: 401(k), 403(b), SEP, SIMPLE, Pension/Profit-Sharing

Key Takeaways

  • Defined benefit (pension) plans promise a formula benefit and place investment risk on the employer; defined contribution plans promise only an input.
  • The 2025 elective deferral limit for 401(k) and 403(b) plans is $23,500, plus a $7,500 catch-up at age 50 and older.
  • 403(b) tax-sheltered annuities serve public schools and 501(c)(3) nonprofits and allow a special 15-year-of-service catch-up.
  • Simplified Employee Pension (SEP) IRAs are employer-funded only, with a 2025 cap of the lesser of 25% of pay or $70,000.
  • SIMPLE IRAs fit employers with 100 or fewer workers; the 2025 deferral limit is $16,500 with a $3,500 catch-up.
Last updated: June 2026

Two Families of Employer Plans

Every employer-sponsored qualified plan is either a defined benefit plan or a defined contribution plan. The distinction governs who carries the investment risk and what the worker is actually promised.

FeatureDefined Benefit (DB)Defined Contribution (DC)
PromiseA specific retirement income (formula)A contribution amount only
Investment riskEmployerEmployee
Final benefitKnown in advanceDepends on contributions and returns
FundingActuarially determinedDefined input each year
PBGC insuranceYesNo

A traditional pension is the classic DB plan. A 401(k), 403(b), profit-sharing, SEP, and SIMPLE are all DC plans.

401(k) Plans

The 401(k) is the dominant private-employer plan. Employees elect to defer salary on a pre-tax (or Roth after-tax) basis, and employers may add a match or profit-sharing contribution.

2025 ItemAmount
Employee elective deferral$23,500
Catch-up, age 50+$7,500
Total annual additions (all sources)$70,000

Worked example: Dana, age 55, defers the full $23,500 plus the $7,500 catch-up, for $31,000 of her own money. Her employer adds a 4% match worth $6,000. Her total additions of $37,000 are well under the $70,000 ceiling, so all contributions are allowed.

A safe harbor 401(k) lets the employer skip the ADP/ACP nondiscrimination tests by promising a set match (for example, 100% of the first 3% plus 50% of the next 2%) that is immediately vested.

403(b) Tax-Sheltered Annuities

A 403(b) plan, historically called a Tax-Sheltered Annuity (TSA), serves a narrow set of employers:

  • Public school systems (K-12 and public universities)
  • 501(c)(3) tax-exempt organizations such as hospitals and charities
  • Certain churches and their employees

Deferral limits mirror the 401(k) ($23,500 elective; $7,500 age-50 catch-up in 2025), but a 403(b) adds a unique perk: the 15-year service catch-up, allowing eligible long-tenured employees to contribute up to $3,000 more per year (subject to lifetime caps).

PlanTypical EmployerSpecial Catch-Up
401(k)For-profit companyNone beyond age-50
403(b)School / nonprofit15-year service catch-up

Exam cue: If the question names a public school teacher or nonprofit hospital employee, the answer is a 403(b), not a 401(k).

Test Your Knowledge

A nurse employed by a nonprofit 501(c)(3) hospital with 20 years of service wants to maximize tax-deferred retirement savings. Which plan and feature should she expect?

A
B
C
D

SEP and SIMPLE Plans for Small Employers

Small businesses and the self-employed favor two streamlined arrangements that fund IRAs rather than trust-based plans.

A Simplified Employee Pension (SEP) IRA is funded only by the employer; employees make no salary deferrals. The 2025 cap is the lesser of 25% of compensation or $70,000. SEPs are flexible — the employer can vary or skip contributions year to year — and require almost no paperwork (no Form 5500).

A SIMPLE IRA (Savings Incentive Match Plan for Employees) suits employers with 100 or fewer workers. Employees defer up to $16,500 (2025), plus a $3,500 catch-up at age 50+. The employer must either match dollar-for-dollar up to 3% of pay or make a 2% non-elective contribution for everyone.

PlanWho Funds2025 LimitEmployer Size
SEP IRAEmployer onlyLesser of 25% pay or $70,000Any
SIMPLE IRAEmployee + employer$16,500 deferral + $3,500 catch-up100 or fewer

Pension and Profit-Sharing Plans

Traditional pension plans are defined benefit arrangements. The employer promises a formula benefit — for example, 1.5% × final average salary × years of service — and must fund it actuarially, bearing all investment risk. The Pension Benefit Guaranty Corporation (PBGC) insures these benefits within limits.

Worked formula: A worker with a final average salary of $80,000 and 30 years of service under a 1.5% factor earns an annual pension of 0.015 × $80,000 × 30 = $36,000 per year for life.

Profit-sharing plans are defined contribution plans where the employer makes discretionary contributions, often tied to profits, up to the $70,000 per-participant ceiling. A money purchase pension is similar but requires a fixed mandatory percentage each year.

PlanContribution StyleRisk Bearer
Defined benefit pensionMandatory, actuarialEmployer
Money purchaseMandatory fixed %Employee
Profit-sharingDiscretionaryEmployee
Test Your Knowledge

Which retirement plan is funded SOLELY by the employer and does NOT permit employees to make salary-deferral contributions?

A
B
C
D

SEP vs. SIMPLE Distinctions

Two small-employer plans are heavily tested. A SEP (Simplified Employee Pension) is employer-funded only into employees' IRAs, with a high contribution limit (a percentage of compensation up to an annual cap), ideal for self-employed and small firms. A SIMPLE plan allows employee salary-deferral plus a mandatory employer match (typically dollar-for-dollar up to 3% or a 2% nonelective contribution), is limited to employers with 100 or fewer employees, and has lower deferral limits than a 401(k).

401(k) Catch-Up and Vesting

401(k) plans allow pre-tax (or Roth) salary deferrals with employer matching; participants age 50+ may make catch-up contributions above the regular limit. Employer contributions follow a vesting schedule (cliff or graded), while employee deferrals are always 100% vested immediately. 403(b) plans serve public-school and 501(c)(3) nonprofit employees with similar deferral mechanics. All these plans require RMDs and impose the 10% early-withdrawal penalty before 59-1/2.

Test Your Knowledge

An employer with 60 employees wants a plan funded by employee salary deferrals plus a required employer match, with minimal administrative cost. The best fit is a:

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B
C
D