No, not all airlines offer an Unaccompanied Minor (UM) service, and policies vary drastically across the industry. Most full-service "legacy" carriers like Delta, United, American, and British Airways provide a mandatory UM service for children (typically ages 5 to 11 or 14) for an additional fee, ensuring a staff member escorts the child from the gate to the aircraft and to the receiving adult. However, many low-cost and ultra-low-cost carriers do not offer this service at all. For example, Ryanair, EasyJet, and Allegiant generally do not allow children under 16 to fly without an adult (18+) on the same reservation. Other airlines, like Southwest, offer the service for ages 5–11 but do not provide an "escort" through the terminal, only supervision on the plane. In 2026, it is essential to check the airline's specific "Minor Policy" before booking, as the fees (ranging from $50 to $150 per flight) and age requirements are strictly enforced for safety and liability reasons.