Most airlines in 2026 permit infants to travel as early as 7 days old, though some, like IndiGo, allow babies as young as 3 days old with a healthy medical clearance. However, pediatricians generally recommend waiting until a baby is at least 3 to 6 months old before flying. This is because a newborn’s immune system is still developing, and the recycled air in a pressurized cabin poses a higher risk of exposure to viral infections. Additionally, the rapid changes in cabin pressure during takeoff and landing can be quite painful for an infant's small ear canals. If you must travel earlier, 2026 health guidelines suggest ensuring the baby has received their first round of core vaccinations. For international travel, even a week-old infant requires their own valid passport, and some countries may require a notarized consent letter if both parents are not present during the journey.