Flying With a 3-Year-Old: Own Seat, Own Bag, New Problems

Flying with a 3-year-old is easier than flying with a two-year-old, but the problems change shape. Your child has a paid seat and can sit in it, follow a simple rule and watch a whole episode, but they may be potty training, have outgrown a nap or be close to the size limit of the travel harness you bought last year. Decide the restraint at home, pack for the bathroom, give them a small bag of their own to carry, and plan the flight around a day that may not have a nap in it. Here is what is new at three, and what you can stop worrying about.

What changes between two and three

At two, the hard part was the seat itself, and my flying with a 2-year-old plan is built around that fight. At three most of it fades: a three-year-old understands “the seat belt light means we stay sitting” and can wait ten minutes for a snack.

What comes in its place:

• The bathroom. Many three-year-olds are newly potty trained, which means they need to go now, on a plane where the toilet is two rows away and the seat belt sign is on.
• The nap. Some three-year-olds still nap and some have stopped. A non-napper on a 6 a.m. flight doesn’t fall asleep at hour two. They just get more tired as the day goes on.
• Size. A tall three-year-old can be close to the upper limits of some restraints, so check the numbers again before you pack.
• Opinions. They will want to carry their own bag and choose the window. Use that.

Booking, airport energy-burning and rationing are in my flying with a toddler guide; this page covers only what is new at three.

Car seat, CARES harness or seat belt?

The car seat. The FAA’s guidance for parents says a child restraint used on board must carry the label “certified for use in motor vehicles and aircraft”, and that your child’s weight and height must be within the manufacturer’s limits for that seat. At three, most children ride in a forward-facing harnessed seat. That is the seat you bring, because you need it in the rental car anyway. My car seat on a plane guide explains how to read the label, measure the width and choose a seat position.

The CARES harness. The FAA describes AmSafe’s CARES as certified for children who weigh 22 to 44 pounds and are up to 40 inches tall, who can sit upright on their own and who have their own seat. It is approved for every phase of flight, including taxi, takeoff and landing, but only on aircraft, not in cars. That height limit is the one to check at three. Measure your child before the trip, not at the gate. The FAA also warns about counterfeit CARES devices sold online and advises buying from the manufacturer, so I’d order it from Kids Fly Safe rather than a marketplace seller.

The seat belt alone. This is legal for a child with their own seat, and many three-year-olds sit well in it. The catch is sleep. A small child asleep in an adult lap belt slides down and sideways, and you end up holding them up for the rest of the flight.

What you cannot use: the FAA says booster seats and backless seats cannot be used during taxi, takeoff or landing. If your child is moving to a booster for the car, the booster goes in the hold. Use the car seat, the CARES harness or the seat belt on board.

Potty training at 35,000 feet

The problem most parents don’t see coming:

• Go at the gate, then again just before boarding, even if they say they don’t need to.
• Go before the seat belt sign comes on for descent. Landing, taxi and waiting at the gate can easily add up to forty minutes when nobody is allowed to stand.
• Warn them about the flush. Aircraft toilets are loud and sudden, and many children are scared of them. Tell them it’s coming and let them leave the cubicle before you flush.
• Pack one full change of clothes for them and a top for you, in a bag you can reach without the overhead bin.
• A folding travel potty seat fits over an aircraft toilet and makes it feel less like falling in. The OXO Tot 2-in-1 Go Potty also works as a stand-alone potty for the car park and the rest stop.

Their own carry-on

At three, a small backpack of their own works much better than it did at two. It gives them a job. Keep it small: a toddler pack like the Skip Hop Zoo backpack holds a few activities, a snack box and a comfort toy, and stays light enough that you are not carrying it by the second corridor. Put one rule on it: the bag stays under the seat in front.

Keep the drip-fed snacks, wipes and spare clothes in yours. My list of airplane activities by flight length covers what to put in both bags.

At airport security, the TSA says children 12 and under can keep their shoes, light jackets and headwear on, and that the backpack, the stroller and the car seat all go through the X-ray.

Boredom, screens and the missing nap

• Book for the nap you still have, or for the morning. If they still nap, an early-afternoon departure can catch it. If they don’t, a morning flight leaves them at their freshest and gets you there before the tired evening.
• Expect an earlier bedtime on arrival. A three-year-old who skipped rest on a travel day usually needs to go to bed earlier, not later. Betteroo’s sample schedules for nappers and non-nappers at three are a useful guide to how much sleep that day still needs.
• Use screens properly. A three-year-old can follow a whole show, which makes a tablet much more useful than it was a year ago. Bring volume-limited headphones they’ve worn at home first, such as the JLab JBuddies Folding, and download everything before you leave home.
• Talk them through the day. The night before, tell them the order: the car, the line, the bags on the belt, the plane, the snack, the show, the landing. The FAA’s Kids’ Corner has short videos made for this.

Nap, quiet time or neither? Betteroo builds a sleep schedule for your child's age, so you know what a travel day can take before you book the flight. Take the 2-minute sleep quiz →

FAQ: flying with a 3-year-old

Does a 3-year-old need a car seat on a plane?

No. Once they have their own seat, the seat belt is legal. A forward-facing car seat labelled for aircraft use holds them more securely, though, especially if your child might fall asleep. The CARES harness is the lighter alternative if your child is within its limits.

Can a 3-year-old use a CARES harness?

Yes, if they fit it. The FAA lists CARES for children who weigh 22 to 44 pounds and are up to 40 inches tall, who can sit upright on their own and have their own seat. Tall three-year-olds can be near the height limit, so measure them before you travel.

Can my child use a booster seat on the plane?

Not for taxi, takeoff or landing. The FAA prohibits booster seats and backless seats during those phases, so check the booster and use the car seat, the CARES harness or the seat belt on board.

How do I handle potty training on a flight?

Go at the gate, just before boarding and before the descent sign comes on. Warn them about the loud flush and keep spare clothes in the bag at your feet.

Should a 3-year-old carry their own bag?

Yes, if it’s small enough to wear all the way through the airport. Keep the snacks and spare clothes in yours.