Southwest Airlines Infant Policy: Tickets, Seats, Bags & Documents

1. Lap infant or purchased seat?

A lap infant usually travels without occupying a separate passenger seat. On some domestic trips there may be no base airfare, but taxes or other charges can still apply. International itineraries often carry a percentage fare, taxes and ticketing requirements even when the baby sits on an adult’s lap. The infant must be added to the reservation and may need a ticket number.

A purchased seat gives the child their own space but does not automatically approve every car seat. The restraint must meet the airline’s standards, fit the aircraft seat and be installed where crew permit. Some rows are unavailable because of airbags, emergency exits or access requirements. A parent should know how to install the device without blocking another passenger.

Ask about the number of infants allowed per adult. One adult generally cannot hold two lap infants at once; a second infant may need a purchased seat and approved restraint or another adult traveler. Aircraft oxygen-mask availability can also limit where lap infants sit.

2. Age, newborn and birthday rules

Very young newborns may be subject to a minimum travel age or may need medical clearance. Premature birth, recent illness or breathing concerns deserve a clinician’s advice because cabin conditions differ from the ground. The airline can explain its paperwork but cannot give personal medical advice.

Use the child’s age on the flight date. If the baby turns two after the outbound flight but before the return, ask whether the return requires a purchased seat and a different fare. On a multi-airline ticket, each operating carrier can apply its own restraint and documentation rules.

Do not enter a different date of birth to force a fare. The airline may request a birth certificate, passport or other proof of age. A mismatch can delay check-in, change the fare or prevent travel.

3. How to add an infant to a Southwest Airlines booking

1. 01

   Choose seats and travelers

   Decide whether the baby will be a lap infant or occupy a purchased seat. Count adults, infants and other children carefully.

2. 02

   Enter the legal identity

   Use the infant’s full name, sex or gender marker where required, nationality and date of birth exactly as shown on travel documents.

3. 03

   Confirm aircraft rules

   Tell Southwest Airlines about a car seat, bassinet request or other child restraint. Ask which rows are eligible and whether preassignment is possible.

4. 04

   Price every segment

   Review infant fare, taxes, seat cost, baggage and partner-airline conditions. International infant tickets may not be free.

5. 05

   Save proof

   Keep the infant ticket number, receipt, seat assignment and written notes about the restraint or bassinet request.

If an adult’s reservation already exists, contact the ticket issuer before adding the infant elsewhere. Separate records can cause check-in and seat problems. A bassinet is usually a request, not a guarantee, and availability can change with aircraft substitutions.

4. Fares, taxes and seating costs

There is no single “baby flies free” rule. A domestic lap infant can be priced differently from an international lap infant. Government tax, airport charge or a percentage of an adult fare may apply. A purchased seat is generally ticketed, although a child discount may exist in some markets. Ask for the total in writing.

If the trip changes, the infant record must move with the adult. Check that the infant is attached to the correct traveler and every replacement flight. A schedule change can separate family seats or replace an aircraft that supported a requested bassinet.

Compare value, not only fare. A seat fee, flexible ticket or nonstop flight can reduce stress. Avoid tight connections when carrying feeding supplies, a stroller and checked equipment.

5. Documents for domestic and international infant travel

Bring the proof of age Southwest Airlines accepts. International travel normally requires the baby’s own passport and possibly a visa or authorization. A parent’s passport does not cover the child. Check validity, photo and name rules well before departure because infant passport processing takes time.

If only one parent travels, border officials may request a consent letter from the other parent. Custody documents, death certificates or notarization may be relevant in some circumstances. Requirements come from governments and can vary by citizenship, residence, transit point and destination.

Keep originals secure and copies accessible. The ticket, passport and visa should use matching names. If surnames differ, carry suitable relationship documents. Do not pack passports, medication or essential feeding items in checked baggage.

• Passport or accepted proof of age
• Visa or electronic authorization
• Parental consent where required
• Medical letter for relevant conditions or medication
• Infant ticket or reservation confirmation
• Child restraint approval information

6. Strollers, car seats, bassinets and baggage

Ask how many child items can be checked without charge and where to collect them. “Gate check” can mean delivery at the aircraft door or at baggage claim depending on the airport. Remove loose accessories, label equipment and photograph its condition before handing it over.

A car seat accepted as checked baggage is not necessarily approved for use in the cabin. Cabin use depends on certification labels, width, installation direction and seat location. Booster seats generally need a shoulder belt and may not work with an aircraft lap belt. Follow crew instructions.

Bassinet positions are limited and usually have weight, length and age limits. Even a confirmed seat near a bassinet may not guarantee the bassinet itself. During turbulence the baby may need to be removed. Carry a backup comfort plan.

Infant baggage allowances can differ between a lap infant and a ticketed child. Review checked allowance, carry-on allowance, diaper bag treatment and liquid-security exceptions. Security officers—not the airline—make the final screening decision.

7. Feeding, liquids and medication

Security rules may allow reasonable quantities of breast milk, formula, baby food and medically necessary liquids, but screening procedures vary by country. Keep them easy to remove and tell the officer what you are carrying. Cooling packs and pumps can have separate rules.

Pack more feeding supplies than the scheduled travel time because delays happen. Bring safe water or plan where it can be obtained after security. Cabin crew may not be able to refrigerate milk, sterilize equipment or heat a bottle to a precise temperature.

Medication should stay in original labeled packaging where practical. Ask a clinician about timing across time zones and whether a medical letter is advisable. Never place critical medicine only in checked baggage.

8. Airport and onboard routine

Arrive early enough to verify the infant ticket, document and child items. Family lanes or preboarding may be available but are not universal. Fold the stroller before the boarding point if instructed and keep a compact essentials bag.

During takeoff and landing, follow crew directions about how the baby must be held or restrained. Do not use an unapproved sleep product, extension or carrier in place of an accepted restraint. Keep hot drinks away from the child and secure loose items before turbulence.

Pressure changes can be uncomfortable. Feeding or a pacifier during descent may help some babies, but seek medical advice for ear illness or recent surgery. Dress in layers because cabin temperature changes.

9. International connections and partner airlines

Each operating airline may use different infant fares, bassinets and restraint rules. A device accepted on the first flight might not fit the next aircraft. Check all segments and leave enough connection time to retrieve or transfer a stroller if required.

Transit countries can require visas or documents even when passengers remain airside. Confirm through official government sources. Also verify whether checked baggage is transferred automatically and where child equipment is delivered.

If a flight is canceled, tell the rebooking agent that an infant is traveling and whether the infant has a seat. Confirm the infant ticket and bassinet or seat request on the new flight; they may not transfer automatically.

10. Family checklist for the final 48 hours

A calm trip starts with realistic expectations. Airline staff can explain operational rules, while medical and border questions should go to the appropriate professional or government authority. Reconfirm close to travel because aircraft, schedules and regulations can change.

Frequently asked questions about the Southwest Airlines infant policy