Editor’s note: This is a recurring post, regularly updated with new information.
One of the easiest ways families can save money on domestic air travel with small children is by having a child fly as a “lap infant.” There is debate about the safety of this practice, but most parents appreciate the savings — and small children often just want to be in their parent’s arms anyway.
Deciding when and how to travel with a baby can be confusing and overwhelming. Here are the rules you need to know regarding lap infants, along with general tips to make flying with a baby easier.
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Lap infant rules
The magic age is strictly ‘under 2’
To qualify as a lap infant, your child must be under 2 years old. The day they turn 2, that free ticket goes out the window.
If you are looking to get away and your child is nearing their second birthday, moving your vacation a month or two earlier could save you money (though flying with a lap infant and a lap toddler are two very different things logistically).
Related: Why you should travel while your baby is an infant
If you have a trip that spans your child’s second birthday, only the outbound flight will be free.
On the return flight, you will be required to purchase your now-2-year-old a seat with a one-way ticket. (The exception: British Airways will give you the return seat at the same infant fare if your child turns 2 on the journey.)
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Be aware that there are times when buying a one-way flight can be more costly than a round trip, so price out both options if your child is going to turn 2 on your trip.
Empty seats and lap infants
Wondering whether your lap infant can snag a free empty seat?
Every passenger dreams of having an empty seat next to them, but when you are flying with a lap infant, this becomes even more valuable. If there is an unoccupied seat next to you, you just scored a seat for your child without having to pay for it.
Related: Flying with a baby checklist
It pays to speak to the gate agents before boarding to ask if a passenger is sitting next to you. If the flight isn’t full, they might help you find a new seat assignment with an empty seat next to it.
If you think you might be able to get an empty seat next to you and have an FAA-approved car seat, bring it to the gate. If you can’t get access to an empty seat to use it, you can always gate-check the car seat for no fee, and it will be waiting for you when you land.
Related: Bring the kids where? 7 vacation destinations that are surprisingly family-friendly
Luggage allowance for lap infants
Infants flying on paid tickets get the same baggage allowance as adults on paid tickets, but that’s not the case when your under-2-year-old is flying for free on your lap.
Children not occupying a paid seat are not given a checked baggage allowance on most U.S. domestic airlines. Their luggage will be checked with the child’s parents’ luggage and will be subject to any extra baggage fees charged by the airline.
Related: How to avoid checked bag fees
Fortunately, families can check car seats, usually without an added cost. Also, strollers can come on board or be gate-checked, depending on size, for no additional fee; they won’t count against your baggage allowance regardless of whether your child is flying as a lap infant or on a paid fare.
For carry-on bags, most airlines will allow you to bring a diaper bag on board in addition to the airline’s regular carry-on allowance. (Note that Alaska Airlines does not extend this generous diaper-bag policy to lap infants.)
The various luggage requirements are why Southwest Airlines is such a favorite airline among families since all passengers flying on paid tickets get to check two complimentary bags per person. As most parents know, when you travel with children, the amount of extra stuff you have to pack can get out of control. Knowing you can check bags for no fee is awesome.
Traveling with more than one lap infant
The strict rule is: One lap infant per adult.
If you are flying as a solo adult and have two or more children under the age of 2 with you, you must purchase a ticket for one of them (and you should also be awarded a gold medal at the other end of the journey).
Two adults traveling together (or even an older teen with an adult) can have two lap children with them, which is great for parents with twins or kids born close together.
However, don’t be surprised if the flight attendant tells you that you cannot sit next to each other in the same row. Because of the limited number of oxygen masks, most aircraft only permit one lap infant per row.
Lap infants are also not allowed in emergency exit rows or the rows directly in front of or behind the exit rows. On some aircraft, there are additional rows that do not permit lap infants.
Related: Your guide to flying with kids of every age
If you are flying with an infant and the aircraft includes bassinets, book that row if you can. Typically, you’ll find bassinets on international flights, but they might also be available on domestic flights with internationally configured aircraft.
Lap infant fares on international flights
Most international flights allow children under 2 to fly as lap children, but with one big difference — it’s usually not 100% free.
Typically, if you’re flying on a revenue ticket, you must pay the taxes and fees for your lap infant plus, in some cases, 10% of the fare. That might not sound like a lot, but it can add up.
Related: The most family-friendly airlines around the world
For example, when I took my then-3-year-old and 11-month-old to London, the paid children’s fare was only $376 round trip.
If I had decided to forgo a seat for my baby and have him fly as a lap infant, the taxes and fees imposed still would have been close to $150. For around $200 more, I was able to get my son his own seat for the seven-hour flights — well worth it to preserve my back and sanity.
Related: Planning award travel with a lap infant
When adding a lap infant to a ticket using miles, the amount you pay varies drastically and depends on the airline.
For example, Aeroplan has long had a flat cost for lap infant award tickets that used to range from $50 to $125, but the program is scheduled to get even better when the new program rolls out. Lap infant ticket awards will cost just 25 Canadian dollars ($18.64) or 2,500 miles.
Others, such as Cathay Pacific, require you to pay up to 25% of the adult fare plus taxes and fees.
In a premium cabin, that can easily be a four-figure number just to hold your baby in your lap. (Note: Air Canada has had some system issues where they’ve been waiving the fee at times.)
Most airlines will charge you 10% of the adult fare on an international ticket, or in the case of British Airways, 10% of the miles redeemed plus taxes and fees. Remember, ticket prices fluctuate, so you’ll want to add your child as a lap infant at the lowest price you see — which may well be when you first book your ticket.
Related: 23 airline car seat and bassinet policies around the world
If you are traveling with a lap infant to somewhere relatively close, like Mexico or the Caribbean, consider JetBlue, Southwest or Alaska. Those airlines don’t charge a percentage of the adult fare for lap infants flying internationally — just taxes.
Contrast this to an airline like United that charges 10% of the fare for lap infants plus taxes and fees even to Mexico (though not to Canada).
Where lap infants can’t sit
In addition to emergency exit rows, or the rows directly in front of or behind the exit rows, some seats are off-limits to infants — especially those who have an assigned seat with a car seat installed.
This is often due to airbags that are installed in some of the lap belts. Most often you will encounter this in some business- or first-class seats or the first row of economy. However, those aren’t hard and fast rules — it simply varies by airline and aircraft.
For example, on United, child safety seats or restraint systems aren’t permitted in United Polaris business class on 767, 777 and 787 aircraft.
Related: Baby-free travel zones
Tips for flying with a baby
Bring identification
Technically, most airlines require you to show proof of age for your lap infant.
This can include a birth certificate, passport or sometimes hospital or immunization records. In reality, most airlines will not ask you for that information unless your baby looks like a toddler who could be past that second birthday. If you plan to travel internationally after your baby is born, you’ll have to get your child a passport, anyway.
If you get to the airport counter and do not have any documentation for your baby, airlines can theoretically require you to purchase a regular seat for your child. Not only can same-day flights be quite expensive, but you also risk the chance of the flight being sold out.
Related: 13 mistakes parents make when traveling with kids
Southwest is notorious for asking for proof of age for everyone, even newborns, so do not leave your documentation at home. It’s smart to carry a copy in your luggage or save a picture of the documentation on your phone so there are no issues.
Time flights with your baby’s sleep patterns
Babies sleep a lot, just not always when you want them to.
Try to book flights coinciding with their sleep schedules. For longer flights, if you can choose a flight that’s close to their bedtime or an overnight red-eye, you may have a better chance of getting them to sleep for a large part of the journey. For shorter day flights, try to time the flight to your baby’s customary nap time.
All that said — an overtired baby can resist falling asleep, especially in a strange environment. You know your baby best, so if you think there’s no shot of them sleeping on a plane through the night, there’s nothing wrong with just going for that daytime flight as rested and prepared as possible.
Related: The definitive guide to surviving jet lag with your baby
Change diapers before boarding
It’s no fun trying to change a diaper in a cramped airplane bathroom, and there’s also the possibility of being delayed on the tarmac. For these reasons, it’s smart to do a quick diaper change before boarding to potentially reduce the number of changes you’ll have to do in flight.
Feed during takeoff and landing
Know how your ears pop on the plane, and you yawn or chew to make the sensation go away? Well, babies haven’t mastered the art of equalizing their own ear pressure, so takeoff and landing can be particularly uncomfortable for them.
Feeding them during this time can help relieve this pressure because the sucking motion they make will help equalize their ears.
Pack extra earplugs
Sometimes no matter what you do, a baby will cry on a plane. You can help make it a little less painful for those around you by bringing and handing out extra earplugs … if you want to. Sometimes parents choose to make small goodie bags as a friendly gesture toward other passengers in the hope of gaining sympathy and understanding.
Do not feel required to do this; it is just an option if it makes you less anxious about the trip.
Figure out seating arrangements beforehand
Before you board, it’s important to plan and figure out the most comfortable way for your baby to sit. Consider where your child is most comfortable: Do they prefer to snuggle up to a human or are they more relaxed in a car seat?
Your child’s seating arrangement comes down to the preference of the parent and child. Just remember that you’ll need to book an airplane seat for your child if you want to guarantee you can put that child in a car seat next to you.
Related: 6 tips for picking the perfect airplane seat every time
Minimum age to fly
The minimum age to fly varies by airline. Some allow you to theoretically fly the same day the baby is born, and others require the baby to be at least a week or two old. Some airlines will also require a doctor’s note giving the go-ahead for those youngest flyers.
Aside from the actual requirements set by the airplane or your doctor, how young is actually too young to fly?
Candice Dye, a pediatrician at the University of Alabama at Birmingham, says waiting until a baby is at least two to three months old is a good idea.
“Since they are vaccinated by this time, they might need less invasive care even if they do fall sick after the flight,” she said.
Of course, there are times when flying with newborn babies simply can’t be avoided, like after an adoption, to visit family or for work reasons.
Related: Tips for flying with a 3-month-old baby
It’s important to consider your child’s immunizations when making travel plans, and it’s better to wait until your infant has received at least some immunizations, if possible.
Bottom line
Although getting a few extra hours of snuggle time above the clouds might not always be the most comfortable way to fly (for adults, that is), it’s a great way to keep travel costs down.
Many babies prefer sitting on their parent’s lap, especially if the mom is nursing anyway, so you might find that buying a seat is ultimately a waste of money.
However, as long as the child is under 2, the final decision is, of course, yours — and that equation can shift as babies grow from lap infants to lap toddlers.
Additional reporting by Summer Hull and Melissa Klurman.