IUL Calculator (Illustrative)
Model how indexed universal life cash value could grow using illustrative cap, participation and floor rates.
Hypothetical illustration only — not a policy illustration. This is a simplified, hypothetical illustration for education only — not a policy illustration and not financial or insurance advice. It ignores the cost of insurance, administrative and rider fees, and surrender charges, which significantly reduce real IUL cash value. The cap, participation and floor rates are illustrative assumptions you set, not any specific carrier's current rates. Consult a licensed insurance professional before making decisions.
An indexed universal life (IUL) policy credits interest based on a stock index's return, but limited by a cap, scaled by a participation rate, and protected by a floor (usually 0%). This calculator credits your premiums each year at that adjusted rate to illustrate cash-value growth — before the policy fees that a real illustration would subtract.
⚠️ Double-check important results. This is an educational estimate, not professional advice — and where it uses a rate, bracket or fee, those change over time. Verify anything you'll rely on, especially in legal, financial, tax or medical matters, and read our full disclaimer. Think a result is wrong? Tell us so we can fix it.
How to Use This Calculator
Enter the annual premium you would pay into the policy and the number of years to model. Then set the index assumptions: the index return you want to test, the participation rate (how much of the index gain the policy credits), the cap (the maximum credited in a good year), and the floor (the minimum, usually 0%, that protects against index losses).
The calculator credits each year's premium at the adjusted rate and compounds the balance. It deliberately shows the gross illustration so you can see how caps and floors shape returns — a real policy would then subtract fees.
How the Calculation Works
IUL crediting is the index return filtered through three limits. First the participation rate scales the index gain — 100% credits the full gain, 80% credits four-fifths of it. Then the cap trims anything above the maximum, and the floor lifts anything below the minimum, so a market loss credits the floor rather than a negative return.
The result is the credited rate for the year. This calculator applies that rate to the accumulating premiums, compounding annually, to illustrate cash value before costs.
credited rate = min(cap, max(floor, index return × participation))
Worked Example
With an 8% assumed index return, 100% participation, a 10% cap and a 0% floor, the credited rate is min(10, max(0, 8 × 100%)) = 8%. Paying $6,000 a year for 20 years at 8% credited grows to about $274,572 before fees.
If the index instead returned 12%, the cap would limit the credit to 10%. If it fell 5%, the floor would credit 0% — no loss, but no gain either. Those limits are the whole point of an IUL, and its trade-off.
What the Result Means and Its Limits
The figure illustrates how caps, floors and participation shape growth — not what a real policy would deliver. Actual IUL cash value is reduced, often substantially, by the cost of insurance, policy and rider fees, and surrender charges in the early years, none of which this simplified model includes.
Carriers also change caps and participation rates over time, and the crediting method (annual point-to-point, monthly, etc.) affects results. Treat this as a teaching tool for the mechanics, and rely on a licensed agent's actual policy illustration for any real decision.
Assumptions and Limitations
- Ignores cost of insurance, administrative fees, rider charges and surrender charges
- Cap, participation and floor are your assumptions, not any carrier's real rates
- Assumes a single annual crediting rate; real methods vary
- Not a policy illustration — for education only
When to Use an IUL Calculator
People weighing an indexed universal life policy use this to model how cash value might grow under a given cap, participation rate, and floor. Run it to understand how an insurer's illustration actually works, compare policy designs, or stress-test optimistic sales projections before committing. It is an educational model — not a policy quote — that helps you ask an agent the right questions.
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Open calculator →Frequently Asked Questions
What is an IUL?
Indexed universal life is permanent life insurance whose cash value earns interest linked to a stock index, limited by a cap and participation rate and protected by a floor. It combines a death benefit with tax-deferred cash-value growth.
What are cap, participation and floor rates?
The cap is the maximum interest credited in a period; the participation rate is the share of the index gain you receive; the floor is the minimum credited, usually 0%, so index losses do not reduce cash value.
Why is my real IUL value lower than this estimate?
Because real policies subtract the cost of insurance, administrative and rider fees, and early surrender charges. This simplified tool shows growth before those costs, which reduce actual cash value significantly.
Is an IUL a good investment?
It is insurance with an investment-linked component, not a pure investment. The floor protects against losses but caps limit gains, and fees are high. Whether it fits depends on your situation — consult a licensed, fee-transparent professional.
Are these the actual rates my carrier offers?
No. The cap, participation and floor here are assumptions you enter for illustration. Carriers set their own rates and can change them. Ask your insurer for their current rates and a full illustration.
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