An income annuity is an annuity contract that is designed to start paying income as soon as the policy is initiated. Once funded, an income annuity is annuitized immediately, although the underlying income units may be in either fixed or variable investments. As such, income payments may fluctuate over time.

An income annuity, also known as an immediate annuity, a single-premium immediate annuity (SPIA), or an immediate payment annuity, is typically purchased with a lump sum payment (premium), often by individuals who are retired or are close to retirement. These annuities may be contrasted with deferred annuities that begin paying out years later. Investors seeking income annuities should have a clear picture of how much income will be received and for how long. Most annuities payout until the death of the annuitant, and some payout until the death of a spouse.