Traveling with children can be quite a different experience than traveling alone. Navigating security, extra bags, boarding the plane, keeping them entertained and myriad other considerations can make flying with youngsters more interesting.

But that’s assuming you can even get on the plane in the first place, which raises the question: Do minors need identification to travel? The short answer is "no" for domestic U.S. travel, but "yes" for international travel.

Whether kids need ID to fly depends on the type of trip you’re taking. To avoid having your vacation sidelined by missing documentation, here are situations where kids can skip having identification when flying and times when it’s required.

Kids don’t need an ID when flying within the U.S.

Domestic travel with an adult

When flying domestically, both the Federal Aviation Administration (FAA) and the Transportation Security Administration (TSA) confirm that kids younger than 18 don't need an ID to travel.

However, the adult they are traveling with needs to have an ID — and most airlines don't allow children to fly solo unless using an airline's unaccompanied minor service.

An adult must have a state-issued driver’s license or identity card, passport or passport card, permanent resident or border crossing card or other forms of federally recognized identification.

If the child is traveling with a non-parent adult, it can be helpful to complete a child travel consent form to deal with questions at security checkpoints.

If flying with a newborn infant, some airlines require additional documentation, such as a medical form. It may also be good to secure a note from a physician or hospital stating that the infant is healthy to travel.

Domestic travel as an unaccompanied minor

If a child is traveling as an unaccompanied minor, they don't need identification, but the adult taking the child to the airport needs to show an ID. However, if the child does have an identification card or passport, it is wise to bring it.

It's also recommended that they carry their birth certificate. Some airlines may require the adult to sign a release form.

Airlines may have their own requirements for unaccompanied minors, so be sure to check with the carrier. For example, American Airlines requires the child to have a form of identification like a passport or birth certificate. The airline also recommends attaching a copy of a form of ID to the child’s clothing as an additional measure.

Kids need an ID when flying internationally

International travel with an adult

Every individual traveling outside the U.S. needs some form of identification. This could be a passport, passport card or birth certificate, depending on the destination.

Even though it’s possible to cross certain borders with a state-issued ID or to take a cruise without a passport, it’s still important to have some form of identification for every traveler. Almost all countries require a passport book, and if there’s a visa required to enter, children will need to apply for it, too.

If traveling to Canada, children under 16 can travel with a birth certificate or other proof of U.S. citizenship. Still, children should apply for their first passport if they plan to travel internationally at some point since it is necessary to visit most countries.

When a minor is traveling with one of their parents, it is wise to have a notarized letter of consent to avoid any issues at border control checkpoints. When a child is under the custody of one parent, custodial documents also work. Having this information is a good practice whether crossing a border by land or air.

International travel as an unaccompanied minor

Similar to when traveling with a parent, unaccompanied children need documentation when flying internationally — typically a passport. There may also be additional requirements.

Some countries require kids traveling solo to have a letter of consent, so be sure to check with the airline and the embassy of the destination country. If connecting via a third country, be sure to verify any documentation that may be needed during transit.

Travel ID requirements for kids recapped

There may be additional measures adults have to take when traveling with children, depending on the destination. When it comes to carrying identification for children, domestic air travel is mostly seamless. But when crossing a border, there’s more complexity — especially if the child is unaccompanied or traveling with only one parent.

Children don’t have to carry identification when traveling domestically, but to play it safe — since airlines may have their own rules — it’s better to have more documentation than needed.