What it means
The insurer holds the money and credits interest at the end of each crediting period, typically a year. If the index rose, the contract credits a share of that rise, and if the index fell, the credited rate is zero rather than negative.
Three levers determine how much of the index gain reaches the account. A participation rate awards a percentage of the index move, a cap sets a hard ceiling on the credited rate, and a spread deducts a fixed amount from the index return before crediting.
The appeal is for savers close to retirement who want some growth without the risk of a large loss just before they stop working. The trade-off is that they will fall well short of the index in strong years, and the index return used usually excludes dividends.
These contracts carry surrender charges, often on a declining scale over six to ten years, so money withdrawn early can incur meaningful penalties. Insurers can also change caps and participation rates on renewal, within limits set out in the contract.
The important nuance is the credit risk. The guarantee is only as good as the insurer standing behind it, which is why the issuer's financial strength deserves as much attention as the headline cap.
In practice
Real-world examples.
Example
A 58-year-old operations manager moves $150,000 from a share portfolio into an indexed annuity, accepting a 5% cap because a large market fall in the five years before retirement would force him to work longer.
Example
A retired couple splits their savings, keeping half in index funds for growth and placing half in an indexed annuity so that a portion of their capital cannot fall in value during a downturn.
Example
A financial adviser compares two indexed annuities for a client. One offers an 8% cap with a 100% participation rate, the other an uncapped rate with a 45% participation rate, and the choice depends on whether the client expects modest or very large index gains.
Formula
Calculation
Credited rate = the lower of the cap and (Index return x Participation rate), with a floor of 0%. New account value = Previous value x (1 + Credited rate).
Suppose an investor places $200,000 in an indexed annuity with a 70% participation rate and a 6% annual cap. In year one the index rises 12%. Index return x participation rate = 12% x 0.70 = 8.4%, which exceeds the 6% cap, so the credited rate is 6%. Interest credited = $200,000 x 0.06 = $12,000, and the account value becomes $212,000.
In year two the index falls 10%. The floor applies, so the credited rate is 0%, no interest is added and the account stays at $212,000. In year three the index rises 5%: 5% x 0.70 = 3.5%, which is below the cap, so $212,000 x 0.035 = $7,420 is credited, taking the balance to $219,420.Case study
Seen in the real world.
Greystone Mutual Assurance is a fictional insurer invented for this illustrative case. It sold a five-year indexed annuity with a 6% cap and full participation to a saver who deposited $250,000 three years before retiring.
Over the five years the reference index returned 14%, then -9%, then 4%, then 21%, then 2%. Credited rates were 6%, 0%, 4%, 6% and 2%, so the account grew to roughly $299,000, an average of about 3.6% a year.
Over the same period the index itself gained about 32% with dividends reinvested. The illustrative point is not that the saver was misled but that they consciously bought a smoother, smaller return, and the two zero years were exactly what they had paid the cap to obtain.
Watch out
Common mistakes.
- Assuming the contract pays the full index return. Caps, participation rates and spreads mean the credited rate is usually well below the index in strong years.
- Overlooking that the index return used almost always excludes dividends, which historically make up a large share of total equity returns.
- Buying an indexed annuity with money that may be needed soon, since surrender charges in the early years can consume a significant slice of the balance.
Questions
People also ask.
Is an indexed annuity an investment in the market?
No, it is an insurance contract whose interest is calculated by reference to an index, and the buyer never owns the underlying shares.
Can the account value go down?
Not from index losses, because of the 0% floor, though fees for optional riders and surrender charges on early withdrawal can still reduce it.
Can the insurer change the cap?
Usually yes at each renewal, within a guaranteed minimum stated in the contract, so it is worth checking that minimum rather than only the current rate.
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