Allegiant permits each ticketed passenger one carry-on bag plus one personal item, such as a purse, briefcase or laptop computer. The carry-on bag can measure up to 9 inches high, 14 inches wide and 22 inches long. The airline will not accept checked baggage that cannot be safely carried in the baggage compartment. Excess baggage charges apply when items have outside measurements that exceed 80 inches, or that weigh more than 50 pounds. Outside measurement equals the sum of the greatest outside length plus the greatest outside height plus the greatest outside width. Baggage in excess of the five-bag maximum is charged an extra $50 per bag. Those wishing to carry large musical instruments on board, such as cellos or bass guitars, must reserve the limited space available ahead of time and are charged a fee.
There are a number of reasons why the airline could refuse to transport a ticketed passenger. Among others, they include passengers who refuse searches or fail to produce positive identification, persons with special medical apparatus including certain oxygen, incubators or respirators, and individuals without an attendant who have disabilities so severe they cannot assist themselves in an emergency. For reasons of comfort and safety the airline might deny transport or remove individuals who are barefoot, unable to use a seat belt or are known to have a contagious disease; who appear intoxicated or under the influence of drugs; or, who have an offensive odor unrelated to a medical condition. Persons whose conduct is known to be disorderly, abusive, offensive, threatening, intimidating or violent may be denied transport. Likewise, the airline may deny travel to manacled persons in custody.
The airline does not provide transportation to infants 14 days or younger without written approval from the infant's attending physician, and all infants must be accompanied by a passenger who is at least 14 years old. A child between the age of 15 days and two years can ride for free if accompanied by a passenger at least 14 years old but there is no guarantee an unoccupied seat for the child will be available. As of November 2009, the airline no longer permitted children age 13 or under to travel unaccompanied
