Do I have to buy a seat to use a car seat on the plane?

Yes. A car seat needs its own ticketed seat to be installed. If you are flying with a lap baby and the flight is not full, some airlines may let you use an empty adjacent seat, but that is never guaranteed. Buying the seat is the only way to be sure you can use your car seat.

Which car seats are FAA approved for planes?

Any car seat labeled "This restraint is certified for use in motor vehicles and aircraft" is approved, which covers most US-sold seats. Boosters are not approved for takeoff and landing. For older children, the CARES harness is the only FAA-approved harness-type device, certified for 22 to 44 pounds.

Can I use a car seat in any seat on the plane?

No. The FAA says car seats generally must go in a window seat, cannot be in an exit row, and must not block another passenger's path to the aisle in an emergency. Reserve the window seat when you book and tell the airline you are bringing a car seat.

What is the CARES harness?

CARES is a lightweight harness that loops around the aircraft seat and clips to the lap belt to add shoulder straps. It is the only FAA-approved harness-type restraint for aircraft, certified for children 22 to 44 pounds and up to 40 inches tall. It is for planes only, not cars.

Will my car seat fit in an airplane seat?

Usually, if it is about 16 inches wide or narrower. Economy aircraft seats are roughly 15 to 18 inches wide, so most car seats fit, but wider seats can be tight. This is airline guidance rather than an FAA rule, so confirm with your carrier and aircraft type.

Family

Using a Car Seat on a Plane

Yes, you can use most car seats on a plane as long as the seat is labeled "certified for use in motor vehicles and aircraft" and you have bought a seat for your child. It installs with the aircraft lap belt, has to go in a window seat, and cannot sit in an exit row. Booster seats are the main exception, since planes have no shoulder belt to make them work.

7 min read Family Updated June 2026

Check the label before you pack

A car seat is only allowed on a plane if it is certified for aircraft. Turn the seat over and look for a label that reads "This restraint is certified for use in motor vehicles and aircraft." Most US car seats carry this, but check yours before the airport, because a flight attendant can refuse a seat without the label.

Using a car seat onboard is also the safest choice. The FAA and AAP both recommend a child under two ride in an approved restraint in their own purchased seat rather than on a lap. Your familiar car seat keeps your baby secure for the whole flight, including turbulence when the seatbelt sign comes on with no warning.

Car seat vs. CARES vs. lap

How the three options compare on a plane.
Option	Who it fits	FAA status	Trade-off
Car seat (aircraft-labeled)	Birth up to the seat's limits	Approved; installs with lap belt	Safest; bulky to carry and needs a bought seat
CARES harness	Children 22-44 lbs, up to 40 in tall	Only FAA-approved harness device for aircraft	Light and packable; not for under 22 lbs and not for cars
Lap baby	Under 2 years	Allowed but not recommended	Free, but no restraint in turbulence
Booster seat	Older children	Not allowed for takeoff or landing	Needs a shoulder belt aircraft seats do not have

The window-seat rule

A car seat has to go in a window seat. The FAA's guidance is that car seats generally must be installed in a window seat, cannot be placed in an exit row, and must not block an escape path in an emergency. The reason is evacuation: a restraint in an aisle seat would slow everyone in the row from reaching the aisle.

Book the window seat next to your own when you reserve, and tell the airline you are bringing a car seat. If your row has more than one small child in restraints, you may need to spread them across rows so no restraint blocks another passenger's exit.

How to install a car seat on a plane

The basics mirror a rear-facing or forward-facing install in a car, using the aircraft lap belt instead of LATCH.

Place the seat in the window position, facing the direction your car seat requires for your child's size.
Route the aircraft lap belt through the car seat's belt path marked in your manual.
Buckle the lap belt and pull it tight; the aircraft buckle sits on top, not threaded into the seat.
Press down on the car seat and remove slack so it does not shift more than an inch side to side.
Recline a rear-facing seat to the angle your manual shows so your baby's head does not slump forward.
Keep your child harnessed in the seat any time the seatbelt sign is on.

The CARES harness for older children

Once your child is too big for a harnessed car seat but you still want more than a lap belt, the CARES harness is the only FAA-approved harness-type child restraint for aircraft. It is certified for children who weigh between 22 and 44 pounds and are up to 40 inches tall, and it weighs about a pound, which beats hauling a car seat through the terminal.

CARES wraps around the seat back and clips to the aircraft lap belt to add shoulder straps. It is approved for aircraft only, not for use in a car, so it does not replace a car seat at your destination. Look for its own FAA approval label that says it is approved for aircraft use.

Why booster seats are out, and which seats fit

Booster seats are not allowed during takeoff and landing on a plane. A booster needs a lap-and-shoulder belt to position it correctly, and aircraft seats have only a lap belt. A child big enough for a booster is also big enough to use the aircraft lap belt on its own, so the FAA simply has them buckle the regular belt.

Fit is the other practical limit. Economy aircraft seats run roughly 15 to 18 inches wide, so a car seat around 16 inches wide or narrower fits most planes. This width guidance comes from airlines rather than an FAA rule, so check your specific airline and aircraft if your seat is on the wide side.

Your car seat or device is not allowed onboard if

It has no label reading "certified for use in motor vehicles and aircraft" (CARES being the aircraft-only exception with its own FAA label).
It is a booster seat or a backless booster; these cannot be used for takeoff or landing.
It is a vest- or harness-type device other than CARES, or a lap-held belly belt, which the FAA prohibits for taxi, takeoff, and landing.
It is too wide for the aircraft seat; confirm width with your airline before you fly.
You did not buy a seat for the child, since a car seat requires its own ticketed seat.

Reflects FAA flying-with-children guidance and Advisory Circular 120-87C, and AAP HealthyChildren, 2024-2026.

Sources & further reading

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This article reflects current AAP, CDC, FDA, and other public-health guidance and is for educational purposes only. It does not constitute medical advice. ParentFlow is a wellness companion — not a substitute for your pediatrician. For any medical concern, contact your healthcare provider.