IBNR and claims reserves for self-funded employers.
A self-funded plan owes claims for care that has already happened but has not yet been billed or paid. That obligation is called incurred but not reported, or IBNR, and understanding it prevents surprises when you change vendors, end a plan or close your books.
What IBNR actually is.
Care Happens Before the Bill
A visit in December may not be billed and paid until February. At any date, some claims have been incurred but are still working their way through.
IBNR Is an Estimate
It is not a fixed number. Actuaries estimate it from payment patterns, called lag, using the plan’s own claims history.
It Belongs on the Plan’s Books
Whether the plan holds a reserve or the employer carries the liability, someone owes the claims. Ignoring it understates the plan’s true cost.
It Changes With Enrollment and Trend
More enrollees, higher cost trend and faster or slower billing all move the number.
It Matters Most at Transitions
Ending a self-funded plan, changing administrators or moving to insured coverage leaves a tail of unpaid claims that needs a funding plan.
Stop-Loss Interacts With It
Whether those claims are reimbursable depends on the stop-loss contract basis and run-out, so the two need to be read together.
The inputs behind a reserve.
We work with our actuarial partners on the estimate. These are the inputs they use.
Claims Lag Triangles
Paid claims are arranged by the month care was incurred and the month it was paid. The pattern shows how much of a month’s claims are still unpaid at each point.
Completion Factors
Applying the observed pattern to recent months estimates how complete each month is, and what remains to be paid.
Seasonality and Large Claims
Large claims and seasonal patterns are handled separately so one unusual month does not distort the estimate.
Enrollment and Trend
Current enrollment and expected trend adjust the estimate to the plan as it is today.
Margin
Reserves often carry a margin for adverse experience, whose size depends on purpose and the plan’s risk.
Professional Standards
Actuarial standards of practice govern how incurred claim liabilities are estimated for health plans.
How we use it in your plan.
Set a Reserve Target With Finance
We work with your finance team and actuarial partners to decide whether and how to hold a reserve.
Plan the Tail Before Any Change
We estimate the run-out cost before a transition so it appears in the decision, not afterward.
Track It Over Time
We monitor claims lag and reserve adequacy against actual payments so the estimate improves.
Three questions to settle.
What Is Our Current IBNR Estimate?
Ask for the figure, the method and the date, and who prepared it.
Who Owns the Liability if We End the Plan?
Confirm in writing who pays the tail and how it will be funded.
How Does Our Auditor Treat It?
Ask your auditor how the liability appears in your financial statements, and plan for it.
Common Questions About IBNR
Do we need to hold a reserve?
There is no single rule for every employer. Many hold some reserve for cash-flow stability. Your auditor and actuary guide the financial reporting side.
Is IBNR the same as run-out?
They are related. IBNR is the estimate of claims incurred but unpaid. Run-out is the period during which those claims are paid after a date.
Does CFH calculate IBNR?
We set these estimates with our actuarial partners. We do not claim in-house actuarial certification.
Does a level-funded plan have IBNR?
The plan still has incurred but unpaid claims at any date. How that shows up depends on the contract and who is holding the funds.
What happens to IBNR if we move to a fully insured plan?
The new carrier covers care after its effective date. Claims from before it remain the old plan’s responsibility, so the tail needs funding.
Does stop-loss pay IBNR claims?
Only if the contract’s basis and run-out cover them. This is one more reason to read the contract with the transition in mind.
Send us your renewal.
We’ll tell you whether it looks competitive, where we see opportunity, and the five questions we’d put to your carrier. No cost, and no obligation to move anything.
The renewal letter
Your current plan summary
Contribution split by tier
Enrolled counts by tier
Four documents — two more if your group is 50 or more. Nothing else; every extra one is a reason to postpone.
Laws and rules referenced
Actuarial Standard of Practice No. 5 — Incurred health and disability claims estimation.
29 U.S.C. § 1104 — Fiduciary duties in managing plan funds and service providers.
This page is general information, not legal, tax or actuarial advice. Rules change and facts matter, so confirm your situation with counsel or a qualified advisor.
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