To purchase long term care insurance, you typically need to be at least 18 years old. However, the ideal age to purchase this type of insurance is generally between 50 and 65 years old. At this age, you are more likely to qualify for coverage and secure more affordable premiums. It's important to note that the cost of long term care insurance increases as you get older, so it's advisable to consider purchasing it earlier rather than later. Additionally, some insurance companies may have specific age requirements or restrictions, so it's best to consult with an insurance agent or company to get accurate and up-to-date information on age requirements for long term care insurance.