401(h) Rules

401(h) Plan Actuarial Valuation: What the Actuary Actually Does

The actuary is the engine room of any 401(h) design. Here's a plain-English tour of what they're modeling and why.

By 401h.com EditorialPublished Jun 15, 2026Updated Jun 15, 202611 min read

Key takeaways

  • The actuary projects retiree medical liability and translates it into funding.
  • Assumptions for cost trend, return, mortality, and turnover all drive the number.
  • The incidental-benefit ratio is monitored as part of the annual exercise.
  • Assumption changes are normal and material.

What the actuary models

The valuation projects the stream of qualifying retiree medical benefits the plan will pay, then values that stream using assumptions for medical-cost trend, investment return, mortality, and participant turnover. The result feeds the funding requirement.

Integration with the underlying plan

401(h) is not modeled in isolation. The actuary integrates the medical stream with the underlying retirement stream so the plan's overall funding picture stays coherent.

The incidental-benefit ratio

Aggregate medical funding compared to aggregate retirement funding is monitored as part of the valuation. Drift toward the ceiling is a signal to revisit design before it becomes a problem.

Frequently asked questions

At minimum annually, consistent with the underlying plan's funding cycle.

Availability, tax treatment, and plan design depend on the facts and circumstances of the employer, plan document, participant group, and applicable law. 401h.com provides general educational information only — not tax, legal, actuarial, investment, or ERISA advice. Consult qualified tax, legal, actuarial, and plan professionals.

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401h.com Editorial

401h.com

The 401h.com editorial team publishes plain-English explainers on 401(h) retiree medical benefit plans. Educational only — not tax, legal, actuarial, investment, or ERISA advice.

Next step

Find out whether a 401(h) strategy may fit

Talk with a 401(h) specialist about your plan, participant group, and retiree medical objectives.

Availability, tax treatment, and plan design depend on the facts and circumstances of the employer, plan document, participant group, and applicable law. 401h.com provides general educational information only — not tax, legal, actuarial, investment, or ERISA advice. Consult qualified tax, legal, actuarial, and plan professionals.