On American, JetBlue, Frontier, Allegiant and Breeze, a lap infant’s diaper bag comes on board free, on top of your own bags. On Delta, Alaska, Hawaiian and Sun Country it counts toward the adult’s allowance, and Southwest gives a lap child no bags at all.
| Airline | On board | Checked bag |
|---|---|---|
| American Airlines | 1 diaper bag per child, on top of your carry-on and personal item | International lap infant: 1 free bag, up to 25 lbs (11 kgs) and 22 x 14 x 9 in (56 x 36 x 23 cm) |
| Delta | No allowance of its own: a lap child’s bags count toward the adult’s | International ticket at 10% of the adult fare: 1 bag up to 20 lbs. (10kg), 45 in in total, plus 1 fully collapsible stroller |
| Southwest | None: a lap child can’t check or carry on any baggage | None |
| Alaska Airlines | A diaper bag counts toward the adult’s carry-on limit | Not stated |
| Hawaiian Airlines | A diaper bag counts toward the adult’s carry-on limit | Not stated |
| JetBlue | 1 diaper bag, on top of your carry-on and personal item | None for a lap infant |
| Frontier | A second personal item, like a diaper bag, at no charge | Not stated |
| Allegiant | 1 diaper bag, on top of 1 carry-on and 1 personal item | Not stated |
| Sun Country | The child’s carry-on counts toward the adult’s | Not stated |
| Breeze | 1 infant bag per infant, outside your carry-on allowance | Not stated |
| WestJet | 1 diaper bag | 2 pieces of infant equipment free |
| British Airways | An extra bag for in-flight essentials | 1 bag of 23kg, except on Basic (hand baggage only) fares |
| easyJet | 1 baby changing bag, up to 45 x 36 x 20 cm, under the seat | Not stated |
| Ryanair | 1 baby bag, up to 5kg and 45x35x20cms | Not stated |
Strollers and car seats are separate from these allowances: see strollers by airline.
With a seat of their own
British Airways books an infant with a paid seat as a child, with the same baggage allowance as an adult. easyJet gives infants with booked seats the same cabin bag and hold luggage allowance as adults.
Breast pumps and breast milk
American doesn’t count a breast pump or a small, soft-sided cooler of breast milk as your carry-on or personal item. JetBlue treats a breast pump as an assistive device, and Frontier lets breast pumps and breast milk come on board in addition to your personal item.
Security rules for formula and milk are on baby formula and breast milk on a plane.