To begin pulling income from an annuity.
When it's time to annuitize, the insurance company may make several options available to the annuitant. Depending on financial need and life situation, he or she may choose to take lifetime payments or payments for a certain period of time only. The insurance company may also make this decision itself.
Most annuity holders never annuitize. Instead, they use an annuity for a while to provide a stream of income, and then move their money elsewhere.
It may or may not be wise to annuitize, depending on factors like age, gender and life expectancy. Talk to a licensed insurance agent for more advice on the topic.