Iced tea does contain caffeine. The main ingredient of iced tea is tea leaves, and these plants naturally contain caffeine. The amount of caffeine contained in a glass or pitcher of iced tea depends on a number of factors.
One particular brand of iced tea, Lipton, reportedly contains 48 milligrams of caffeine per 20-ounce bottle. There is actually a wide variety of caffeine levels in tea, depending on whether iced tea is pre-bottled or steeped at home, states Mayo Clinic. Instant iced tea can have anywhere between 11 and 47 milligrams per 8-ounce serving. Ready-to-drink bottled varieties contain between 5 and 40 milligrams per 8 ounces.