How Annuities Work

The Basic Idea

At its core, an annuity is a contract with an insurance company. You give the insurer a sum of money — either all at once or over time — and in return, the insurer agrees to pay you income, either now or in the future. The terms, payment amounts, and growth potential depend on the type of annuity you choose.

The Two Phases of an Annuity

Step-by-Step: How an Annuity Works

1. You fund the annuity. You contribute a lump sum, transfer money from another retirement account, or fund it with multiple payments over time.
2. Your money grows. The insurance company credits interest, index-linked gains, or investment returns based on the contract you choose. Growth is tax-deferred until withdrawn.
3. You decide when to take income. With an immediate annuity, income begins right away. With a deferred annuity, you choose a future start date — sometimes years or even decades later.
4. The insurer pays you income. Payments can be guaranteed for a set period or for the rest of your life. Some annuities also offer inflation adjustments or spousal continuation.
5. Beneficiaries may receive remaining value. Depending on the contract and options selected, any remaining account value can pass to a named beneficiary.

Key Features That Affect How an Annuity Works

Why Understanding the Mechanics Matters

Knowing how an annuity actually works helps you compare options, evaluate whether the guarantees match your retirement goals, and avoid surprises later. The right annuity isn't about chasing the highest rate — it's about choosing the structure that supports your income plan.