A registered index-linked annuity (RILA) — often called a buffer annuity or structured annuity — is a deferred annuity that credits returns based on a market index, offers partial protection against index losses, and can genuinely lose value. That last part matters: unlike a fixed or fixed indexed annuity, a RILA is a security, registered with the SEC and sold by prospectus, because your principal is at risk.
RILAs exist to fill the gap between two older designs. A fixed indexed annuity protects principal completely but limits upside tightly; a variable annuity offers full market exposure with full market risk. A RILA splits the difference — you accept some downside in exchange for meaningfully more upside than an FIA can offer.
How a RILA Credits Interest
You allocate your premium to one or more crediting segments, each defined by four choices:
- An index — commonly a large-cap benchmark like the S&P 500, though carriers offer others.
- A term — the measurement period, often one, three, or six years.
- An upside limit — a cap (maximum credited return) or a participation rate (a percentage of the index gain you receive).
- A protection level — a buffer or a floor that determines how index losses are shared between you and the insurer.
At the end of each term, the insurer measures the index change, applies the cap or participation rate to gains — or the buffer or floor to losses — and adjusts your account value. You don't own the index or any fund tracking it; the return is a contractual calculation, and index dividends typically aren't included.
Buffers vs. Floors: The Two Protection Designs
How a Buffer Works
A buffer means the insurer absorbs the first portion of an index loss and you take the rest. With a hypothetical 10% buffer: if the index falls 6%, you lose nothing. If it falls 10%, you still lose nothing. If it falls 30%, the insurer absorbs the first 10 points and your account falls 20%. Buffers protect you fully in ordinary downturns but leave the tail risk — the deep crash — on your side.
How a Floor Works
A floor is the mirror image: you absorb losses down to the floor, and the insurer absorbs everything beyond it. With a hypothetical -10% floor: an index drop of 6% costs you 6%, a drop of 10% costs you 10%, and a drop of 30% still costs you only 10%. Floors expose you to every modest downturn but put a hard limit on your worst case.
The table below shows the same hypothetical index outcomes under each design, ignoring caps and fees for clarity:
| Index result for the term | Your loss with a 10% buffer | Your loss with a -10% floor |
|---|---|---|
| Down 6% | 0% | 6% |
| Down 10% | 0% | 10% |
| Down 20% | 10% | 10% |
| Down 30% | 20% | 10% |
Neither design is better in the abstract. A buffer suits someone who expects normal volatility and wants routine dips absorbed; a floor suits someone whose real fear is the once-a-decade crash. Buffer and floor levels, caps, and participation rates all vary by product and change over time — the prospectus and current rate sheet govern, not any example in an article.
Where a RILA Sits: Between an FIA and a Variable Annuity
The cleanest way to place a RILA is on a risk ladder with its two neighbors:
- Fixed indexed annuity (FIA): 0% floor in a typical contract — index losses never touch your account value, but caps and participation rates are the tightest of the three. See how fixed index annuities work and current FIA products and crediting strategies.
- RILA: partial protection through a buffer or floor, with higher caps and participation rates than an FIA because you share the downside.
- Variable annuity: full market exposure through subaccounts, no built-in protection, plus its own fee stack. See what a variable annuity is and how its fees work.
Regulators treat the boundary the same way: FIAs are insurance products, while RILAs and variable annuities are securities. If an FIA's total principal protection matters more to you than upside, the fixed index annuity vs. fixed annuity comparison walks through the fully-protected end of the spectrum.
What "Registered" Means for You
Because a RILA can lose value, it's registered with the SEC like other securities. Practically, that means you'll receive a prospectus that spells out every crediting option, protection level, fee, and surrender term — and the person selling it must hold a securities license, not just an insurance license. Read the prospectus sections on the buffer or floor mechanics and on what happens if you withdraw mid-term; interim withdrawals are often valued under a separate formula rather than the full crediting calculation.
Taxes and Liquidity
The tax treatment is standard deferred-annuity treatment: growth is tax-deferred, withdrawn gains are taxed as ordinary income, and the taxable portion of withdrawals before age 59½ generally owes a 10% additional federal tax. Our guide to annuity taxation covers the mechanics for both non-qualified and IRA-held contracts.
Liquidity works like other deferred annuities: a surrender period with declining charges, often a penalty-free annual withdrawal allowance, and sometimes a market value adjustment. Many RILAs charge no explicit annual fee — the insurer earns its margin through the caps and spreads — though optional riders such as enhanced death benefits carry stated costs.
Who a RILA Fits
- Growth-minded pre-retirees who want more upside than an FIA allows but can't stomach — or can't afford — a full bear-market drawdown close to retirement.
- Investors de-risking a portfolio who would otherwise hold equities and are willing to trade some upside for a defined loss-sharing arrangement.
- People comfortable with moving parts — choosing indexes, terms, and protection levels, and re-evaluating at each term's end.
It's a poor fit for anyone who cannot accept losses at all — that's what MYGAs and FIAs are for, and our MYGA explainer covers the fully guaranteed alternative. It's also a poor fit for money needed during the surrender period, and for investors with long horizons and strong risk tolerance, who may prefer low-cost market investments without caps.
Next Step: Evaluate Specific Products, Not the Category
RILAs vary more from product to product than almost any other annuity type — the same carrier may offer buffers and floors at several levels, each with different caps that reprice regularly. Browse our annuity reviews by carrier and product, which include registered index-linked products, and compare what fully guaranteed alternatives are paying on the live best annuity rates page — the right question is rarely "is a RILA good?" but "is this RILA's cap worth this RILA's downside, versus what a guaranteed product pays today?"
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