https://www.united.com/web/en-US/content/travel/baggage/infant.aspx Strollers and car seats United accepts one stroller and one car seat free of charge for each child, including children under the age of two traveling on an adult's lap and infants traveling internationally on 10 percent of an adult fare. If requested by the customer, United can check strollers at the departure gate. United is not liable for damage to strollers. Customers cannot purchase excess valuation for strollers. Note: Wagons and similar products are not considered strollers. Customers who bring them to the airport will need to check them as part of their checked baggage allowance before passing through security.
Strollers and car seats
United accepts one stroller and one car seat free of charge for each child, including children under the age of two traveling on an adult's lap and infants traveling internationally on 10 percent of an adult fare.
If requested by the customer, United can check strollers at the departure gate. United is not liable for damage to strollers. Customers cannot purchase excess valuation for strollers.
Note: Wagons and similar products are not considered strollers. Customers who bring them to the airport will need to check them as part of their checked baggage allowance before passing through security.
美国国内航班我托运过,因为我不想带着座椅在航站里面走到登机口给地勤,不过国际航班我没有托运过,不知道有无不同规则.