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

Key Takeaways

  • Defined benefit (DB) plans promise a formula-based benefit and put investment risk on the employer; defined contribution (DC) plans fund an account and put risk on the employee.
  • The 2025 elective deferral limit for 401(k) and 403(b) is $23,500, plus a $7,500 catch-up at 50 and an $11,250 enhanced catch-up at ages 60-63.
  • 403(b) Tax-Sheltered Annuities serve public schools and 501(c)(3) nonprofits and add a 15-year service catch-up of up to $3,000.
  • SEP plans are employer-funded only (up to 25% of pay or $70,000); SIMPLE plans allow employee deferrals of $16,500 with a required employer match or 2% non-elective contribution.
  • Safe harbor 401(k) designs use specified employer contributions to automatically pass ADP/ACP nondiscrimination testing.
Last updated: June 2026

Two Families: Defined Benefit vs. Defined Contribution

Every employer plan is either a defined benefit (DB) plan or a defined contribution (DC) plan. The exam hinges on who bears the investment risk and what is promised.

FeatureDefined Benefit (DB)Defined Contribution (DC)
What is promisedA specific benefit (formula)A contribution amount
Investment riskEmployerEmployee
Benefit known in advanceYesNo -- depends on returns
FundingActuarial, employer-fundedSet contributions
Pension Benefit Guaranty Corporation (PBGC) insuranceYesNo
ExamplesTraditional pension401(k), profit-sharing, SEP, SIMPLE

A classic DB final-average formula might be 1.5% x final-5-year-average salary x years of service. With a $100,000 average salary and 30 years: 0.015 x $100,000 x 30 = $45,000 per year for life -- a benefit the employer must fund regardless of market performance.

401(k) Plans

The 401(k) is the dominant private-sector DC plan. Employees defer salary pre-tax (or Roth after-tax), and employers often match.

Feature (2025)Detail
Employee elective deferral$23,500
Catch-up at age 50+$7,500
Enhanced catch-up ages 60-63$11,250
Total annual additions (all sources)$70,000

Nondiscrimination Testing and Safe Harbor

Standard 401(k)s must pass the Actual Deferral Percentage (ADP) and Actual Contribution Percentage (ACP) tests so HCEs do not defer far more than rank-and-file workers. A safe harbor 401(k) automatically passes these tests if the employer makes a required, immediately vested contribution.

Safe Harbor OptionEmployer Contribution
Basic match100% of first 3% + 50% of next 2%
Enhanced match100% of first 4%
Non-elective3% of pay to all eligible employees

Match math: An employee earning $80,000 defers 5%. A basic safe harbor match gives 100% of the first 3% ($2,400) plus 50% of the next 2% ($800) = $3,200 of employer money.

403(b) Tax-Sheltered Annuities

A 403(b), also called a Tax-Sheltered Annuity (TSA), is the nonprofit-sector cousin of the 401(k). Eligible sponsors are:

  • Public schools (K-12, colleges, universities)
  • 501(c)(3) tax-exempt organizations (charities, hospitals)
  • Churches and certain ministers
Feature (2025)Detail
Elective deferral$23,500
Age 50+ catch-up$7,500
15-year service catch-upUp to $3,000 extra (lifetime cap $15,000)
Total additions$70,000

Investments are limited to annuities (fixed and variable) and mutual fund custodial accounts, which is why insurance producers see 403(b) business so often.

Exam Tip: If the participant is a public-school teacher or hospital nurse, the plan is a 403(b), not a 401(k). The 15-year catch-up is unique to 403(b)s.

SEP and SIMPLE Plans (Small Employer)

Small businesses use simplified plans that avoid heavy administration.

Simplified Employee Pension (SEP-IRA)

Feature (2025)Detail
ContributionsEmployer ONLY
LimitLesser of 25% of pay or $70,000
Self-employed effective rate~20% of net self-employment income
Form 5500 filingNot required
FlexibilityAmount can vary year to year

SIMPLE IRA (Savings Incentive Match Plan for Employees)

For employers with 100 or fewer employees; the employer may not maintain another qualified plan.

Feature (2025)Detail
Employee deferral$16,500
Age 50+ catch-up$3,500
Enhanced catch-up 60-63$5,250
Employer matchDollar-for-dollar up to 3% of pay, OR
Employer non-elective2% of pay for all eligible employees
Early-withdrawal trap25% penalty if withdrawn within the first 2 years

Trap: SEP contributions are employer-only -- employees cannot defer salary into a SEP. SIMPLE plans do allow employee deferrals.

Pension and Profit-Sharing Plans

Two more DC designs round out the chapter:

  • Profit-sharing plan: Employer contributions are discretionary -- the company decides each year, often tied to profits -- up to 25% of covered payroll and the $70,000 per-participant cap. Good fit for businesses with uneven cash flow.
  • Money purchase pension plan: Contributions are a fixed, mandatory percentage stated in the plan document, owed even in bad years. It trades flexibility for predictability.
PlanContribution StylePer-Participant Cap (2025)
Profit-sharingDiscretionary, can be $0 in a year$70,000
Money purchaseFixed % required every year$70,000
Defined benefitActuarially determinedBenefit cap $280,000/yr

Both DC designs use the standard ERISA vesting schedules (3-year cliff or 6-year graded) for employer money, while a traditional DB pension is insured by the PBGC -- a guarantee that does not extend to any DC plan.

Test Your Knowledge

A registered nurse at a 501(c)(3) nonprofit hospital wants to defer salary into her employer's retirement plan and may also use a special 15-year service catch-up. Which plan is this?

A
B
C
D
Test Your Knowledge

Under a basic safe harbor 401(k) match (100% of the first 3% plus 50% of the next 2%), how much employer match does an employee earning $80,000 receive if she defers 5% of pay?

A
B
C
D