Fixed index annuities work by crediting interest tied to the movement of a stock market index, such as the S&P 500, while guaranteeing your account value cannot fall because of a market decline. The insurance company holds your premium in its own portfolio and uses the index only as a formula for calculating how much interest to add each year. Because you never own the underlying stocks and the insurer bears the investment risk, these contracts are regulated as insurance products under state law rather than as securities under federal law.1U.S. Securities and Exchange Commission. Registration for Index-Linked Annuities and Registered Market Value Adjustment Annuities That distinction shapes how interest is credited, how your money is protected, and how hard it is to get out early.
How Interest Is Calculated
Your contract references a third-party index, but the insurer never buys shares of the stocks in it on your behalf. At the start of each crediting period the company records the index level and compares it to the level at the end of the period. The most common approach is the point-to-point method: the insurer looks at the index on day one and again on the final day of the term, often one year later.2Pacific Life Insurance Company. Understanding Fixed Indexed Annuity Interest-Crediting Methods Some contracts use monthly averaging instead, tracking the index at each month-end and averaging those values to smooth out short-term swings.
One point often missed at purchase: these contracts track price-return indexes, so dividends are excluded from the calculation. Dividends have historically added roughly two percentage points to the S&P 500’s annual return. Over the 20 years ending in 2024, the S&P 500 returned about 8.2% annually on price alone versus 10.4% with dividends reinvested. That gap compounds, and it means the interest credited to your account will always trail the index’s total return even before any other adjustments are applied.
Caps, Participation Rates, and Spreads
After the index change is measured, the insurer applies one or more adjustments that limit how much of that gain reaches your account. Three tools do this work, sometimes in combination.
- A cap sets a hard ceiling on the interest you can earn in a single crediting period. If the index rises 12% and your contract has a 5% cap, you get 5%.
- A participation rate credits a percentage of the index gain. An 80% participation rate on a 10% index gain produces an 8% credit.
- A spread (sometimes called a margin) is a flat percentage deducted from the index gain before interest is applied. A 9% index gain with a 2.5% spread produces a 6.5% credit.3FINRA. The Complicated Risks and Rewards of Indexed Annuities
Some contracts stack these. A participation rate might be applied first and a spread subtracted from the result. When comparing contracts, evaluate all three factors together — a high cap paired with a low participation rate can produce less interest than a lower cap with full participation.
The insurer only guarantees these rates for the initial crediting period, usually one year. At the start of each new term the company can reset the cap, participation rate, or spread within the limits written into the contract. Your disclosure documents show both the current rates and the minimum guaranteed levels the insurer must honor for the life of the contract.4National Association of Insurance Commissioners. Annuity Disclosure Model Regulation
The Annual Reset
Most fixed index annuities use an annual reset, sometimes called a ratchet. At the end of each crediting period, any interest earned locks into your account value, and the index starting point resets to the current level. A later market decline cannot claw back gains you have already earned. If the index drops during a crediting period, no interest is credited for that period, but your locked-in balance stays intact. The reset also means you start each new year from wherever the index is now, so the market does not have to climb back to a prior high before new interest can accrue.
The 0% Floor and What It Actually Protects
The core safety feature is the 0% interest floor. In any crediting period where the index declines, the insurer credits zero interest rather than applying a loss. Your account value stays flat. This guarantee protects both your original premium and all previously credited interest from market-driven losses.
State law adds another layer. Every state requires insurers to follow the Standard Nonforfeiture Law for Individual Deferred Annuities. Under that framework, the minimum value the insurer must maintain is based on at least 87.5% of your premiums, accumulated at a minimum interest rate.3FINRA. The Complicated Risks and Rewards of Indexed Annuities That minimum rate is tied to the five-year Treasury rate, reduced by 1.25 percentage points, with a floor of 1%.5National Association of Insurance Commissioners. Standard Nonforfeiture Law for Individual Deferred Annuities Even in a worst case where the index never posts a gain, holding the contract to maturity guarantees you at least 87.5% of your premiums plus modest accumulated interest.
Important boundary: the 0% floor blocks market-driven losses only. It does not shield you from surrender charges. If you pull money out early, the amount you receive can be less than what you originally paid in.
Surrender Charges and Getting Money Out Early
These are long-term contracts, and the surrender charge schedule is how insurers enforce that. Withdraw more than the free amount during the surrender period and the insurer deducts a percentage-based charge from the excess. Surrender periods typically run six to ten years, and some contracts extend to twelve.6Investor.gov. Surrender Charge The charge usually starts at 7% to 10% in year one and drops by about a point each year until it reaches zero.
Most contracts include a free withdrawal provision letting you take up to 10% of your account value annually without a surrender charge. Not every contract does, so check the specific terms.
Some contracts add a market value adjustment (MVA) that raises or lowers your surrender value based on interest rate changes since purchase. The relationship is inverse. If rates have risen since you bought the contract, the MVA reduces your payout; if rates have fallen, it increases it. The MVA applies only to withdrawals above the penalty-free amount during the surrender period, and in a rising-rate environment it can add a meaningful cost on top of the surrender charge itself.
Taxes on Growth and Withdrawals
Interest earned inside a fixed index annuity grows tax-deferred. You owe no income tax on the credited interest until you take money out, and when you do, the taxable portion is treated as ordinary income rather than capital gains.7Internal Revenue Service. Publication 575, Pension and Annuity Income
For non-qualified annuities purchased with after-tax money outside a retirement account, withdrawals follow an earnings-first rule. The IRS treats each withdrawal as coming from accumulated interest before touching your principal, so you owe income tax on every dollar you pull out until all the earnings are gone. Only then do withdrawals come from your tax-free principal.8Office of the Law Revision Counsel. 26 U.S. Code 72 – Annuities; Certain Proceeds of Endowment and Life Insurance Contracts For qualified annuities funded with pre-tax dollars, such as an IRA rollover, the entire withdrawal is taxable because there is no after-tax basis.
Take money out before age 59½ and the IRS adds a 10% penalty on the taxable portion.8Office of the Law Revision Counsel. 26 U.S. Code 72 – Annuities; Certain Proceeds of Endowment and Life Insurance Contracts Exceptions include distributions after the owner’s death, distributions due to disability, and payments structured as substantially equal periodic payments over your life expectancy.9Internal Revenue Service. Additional Tax on Early Distributions From Retirement Plans Other Than IRAs Stack the 10% penalty on top of the insurer’s own surrender charges and early access becomes expensive fast.
Optional Lifetime Income Riders
Many fixed index annuities offer an optional guaranteed lifetime withdrawal benefit (GLWB) rider for an annual fee, typically 0.80% to 1.25% of the contract value. The rider guarantees you can withdraw a fixed percentage of an “income base” every year for life, regardless of how the actual account value performs.
The income base is not your account value. It is a separate figure used only to calculate rider payments, often the higher of your current account value or the highest value the account reached on any prior contract anniversary. Some contracts also grow the income base by a guaranteed annual percentage during a deferral period, even when the index produces no gains. The withdrawal percentage the insurer allows depends on your age when you start taking income, with older starting ages producing a higher percentage.
The rider fee comes out of your actual account value each year, which drags on accumulation. If you never activate the rider, you have paid the fee for nothing. Because the fee compounds, calculate whether the guaranteed income floor is worth the reduction in growth.
Turning the Contract Into Income
When you are ready to draw income, you have two broad paths: annuitization or systematic withdrawals.
Annuitization converts your account value into a stream of payments from the insurer, typically for life. Once you annuitize, the decision is generally irreversible; you give up the lump sum in exchange for guaranteed periodic payments. Common options include:
- Life only pays the highest monthly amount but stops at your death. If you die early, the insurer keeps the remaining balance.
- Life with period certain pays for your lifetime but guarantees a minimum number of years, often 10 or 20. If you die during that period, your beneficiary receives the remaining payments. The monthly amount is lower than life only.
- Joint and survivor covers two lives, usually you and a spouse, and payments continue until both have died. Monthly payments are smaller because they must cover two lifetimes. Some contracts let you choose whether the survivor receives 50%, 75%, or 100% of the original payment.
Systematic withdrawals let you take money out on a schedule you choose without converting to an irrevocable stream. You keep control of the balance and can change or stop the withdrawals. The tradeoff is that you bear the risk of outliving your money, unless a GLWB rider is in place.
The Free-Look Period After Purchase
After the insurer issues the contract, a mandatory free-look period begins. This window is at least 10 days in most states and up to 30 days in some, and it gives you time to read the full contract and cancel for a complete refund if you change your mind.10Investor.gov. Variable Annuities – Free Look Period Once it expires, the contract terms become binding and surrender charges apply to any early withdrawal. If anything in the delivered contract does not match what you were told at sale — caps, participation rates, rider terms, surrender schedule — the free-look period is when to act.