One adult may only hold one infant under the age of two on their lap. This is a firm safety rule tied to the number of oxygen masks available. So if you’re a solo parent flying with twins and you arrive at the airport with two babies and no extra companion, they simply won’t let you board.
The only real way around this situation is to buy the second child their own full seat. On that seat you then place a certified car seat that the airline approves. It saves you a whole lot of stress right from the planning stage.
You’ll learn exactly how to handle the airport logistics with just your own two hands. I’ve also put together tips on the documents you’ll need when grandma travels with you or when the children have a different surname than you.
TL;DR
- The 1:1 rule is non-negotiable: One adult may only be responsible for one lap infant under 2.
- Twins under two: A solo parent won’t be allowed to fly with them without a second adult or buying a dedicated seat with a car seat.
- New liquid rules: At some airports with new CT scanners the limit has risen to 2 litres, but many terminals still enforce the old 100 ml rule — always check before you fly.
- Family seating law: A revised EU regulation from July 2026 guarantees free seating for children up to 14 next to a parent, but in practice it won’t take effect until mid-2027.
- Travel consent: If you have a different surname than your child, or they’re flying with grandma, an officially certified letter will save you from trouble.
- Delays and compensation: For children under 2 without their own seat ⚠️ practice is inconsistent and airlines often reject claims.
- Companion age varies: With Ryanair only someone over 18 can help you with the second child, while with Wizz Air 16 is enough.
10 Things You Must Know
Let’s now take a look at what you should watch out for and what you really need to know.
1. One infant per adult rule
💡 Tip: This is the absolute basic that wrecks a lot of plans. One adult may only hold one infant (a child under 2) on their lap. If you’re a solo parent with twins who haven’t turned two yet, you simply won’t be able to fly the standard way.
The reason isn’t that airlines want to torment you — it’s pure safety on board. Above each window seat there are exactly two oxygen masks. On top of that, one adult physically couldn’t safely secure two children against their body during turbulence or an emergency.
That’s why low-cost carriers like Ryanair always seat the adult with an infant by the window. If you try to book one adult and two lap infants, the reservation system will block you outright and won’t let you reach payment.
2. What to do when a second adult can’t fly
💡 Tip: If you simply have to fly alone with both children under 2, you basically have only one practical option. You must buy the second child their own seat at the full adult fare.
For that, though, you absolutely need to bring your own certified aircraft car seat on board to put the second child in. The car seat must carry a visible label showing it’s approved for air travel. With some carriers you even have to book this specific seat over the phone via the call centre, because the online system won’t let you do it.
⚠️ A crucial warning: in some jurisdictions the rules are even stricter, and even the car seat option won’t be allowed at all for a solo parent with two infants. Before making any booking in this setup, it’s absolutely essential to call the specific airline’s customer line and have the procedure confirmed.
3. Minimum age of the accompanying person by airline
💡 Tip: The second option for twins is to bring a companion along. But it’s not the same who you take, because the age of the accompanying person differs quite significantly between airlines.
If you’re flying Ryanair and want an older sibling to take the second child on their lap, they must be at least 18. Wizz Air, on the other hand, is more lenient here and accepts 16 as a full adult companion.
Always check these limits in the conditions of carriage before you buy. From the age of 16 low-cost carriers do allow solo travel, but taking responsibility for an infant on your lap is a whole different category from a safety point of view.
4. Flying with grandma or another relative
💡 Tip: What if neither parent is flying and you’re sending your child to the seaside with grandma or an aunt? The airlines themselves usually don’t have the slightest problem with it. Some carriers explicitly state that they place no restrictions on flying with someone else’s child.
In the same breath, though, they point to the rules of the destination country, and that’s where a huge problem can arise. The key is to equip grandma with written consent from the legal guardians for the child’s travel, ideally in two languages.
⚠️ The exact form of the document needs to be verified directly with the relevant authorities. In general, it’s strongly recommended to have an officially certified signature on this document, especially if grandma is flying with the child outside the European Union.
5. Different surnames and the other parent’s consent
💡 Tip: A common reality today is that the mother has one surname and the child has the father’s surname. To you it’s perfectly normal, but at passport control it can be a potential red flag and a suspicion of child abduction.
That’s why you should always carry a copy of the child’s birth certificate — in practice it turns out to be an invaluable tool at airports. It stops unnecessary questioning before it even begins.
The second common snag is the photo on the document itself. A child at three months looks completely different than at three years. A significant change in appearance is a solid reason to get a new document, even if the old one is still technically valid — so don’t let the office brush you off.
6. Divorced parents and shared custody while travelling
💡 Tip: This is by far the most sensitive topic of the whole issue, and parents debate it endlessly in online forums. If you’re divorced and flying to the seaside with your child, do you need the other parent’s consent?
Practically speaking: ⚠️ whether this consent is a mandatory document within the European Union and the Schengen area needs to be checked in advance with a lawyer or the relevant authorities. Border control may still want to see it, especially if you’re flying outside Schengen to countries such as Turkey or Egypt.
⚠️ But if it’s a significantly longer stay, or even a move abroad without consent, it may meet the criteria of international child abduction. That’s very thin ice — so for peace of mind, always get certified consent from the other parent with the exact dates and destination.
7. Practical solo-parent logistics at the airport
💡 Tip: When you’re flying alone with a toddler plus an older child, you need a proper system. The key to success is completely free hands, so a large carry-on backpack on your back is ideal.
An ergonomic baby carrier has proven itself brilliantly in practice. Not only does it free up your hands, but the great news is that a carrier usually doesn’t count towards your luggage at all. With easyJet you’re even explicitly allowed to bring a baby carrier free of charge as one of two pieces of child equipment to check in.
You’ll sweat the most at the security check, because you have to fold the pushchair and take out your electronics. So always use the priority lane for families with children, which most airports thankfully offer without any fuss.
8. Tricky limits on liquids and pushchairs
💡 Tip: Packing liquids for kids is a nightmare, but the situation is changing. Many airports have rolled out new CT scanners, so at those terminals you can bring one container of up to 2 litres extra and don’t even have to take it out of your bag.
⚠️ But be extremely careful, because not all terminals are covered by this change and many still enforce the old 100 ml limit — often the very terminals from which Ryanair and Wizz Air fly to non-Schengen destinations. Baby food and milk thankfully always get an exemption in the amount needed for the journey; that’s governed by the airport’s rules, not the airline’s.
As for the pushchair, if you’re flying with a stricter carrier, remember their firm rule. An unpacked pushchair won’t be covered if it gets damaged. A bag or a solid cover isn’t a recommendation — for them it’s a hard condition.
9. What to pack and what to skip
💡 Tip: Keep things to the absolute minimum. The European Union Aviation Safety Agency (EASA) recommends that children under 12 always sit next to their accompanying person, but with low-cost carriers you have to watch this carefully and possibly pay extra.
Into the backpack, pack mainly new, unfamiliar toys and plenty of favourite snacks, which help equalise the pressure in the ears during descent. On the other hand, absolutely avoid experimenting with sleep medication.
A question that keeps popping up in forums is the artificial sleep hormone. Remember that melatonin must not be given to children under 2, and for older children it’s only possible after very careful consultation with your doctor.
10. Mental prep and what helps the most
💡 Tip: Be ready for plans to fall apart. Our return flight to Faro was delayed, our carefully crafted sleep plan completely collapsed, and Jonáš was awake the whole time. It was fine anyway — he loved the plane and happily gazed out the window.
On another flight to Paris he didn’t want to be strapped into the child belt at all during takeoff and landing, which took a lot of patience. If a flight is delayed by more than 3 hours, compensation comes into play. ⚠️ For children under 2 without their own seat, practice is inconsistent and airlines unfortunately often reject these claims.
And when a wrecked pushchair rolls out at the belt? You must report the damage in writing within 7 days under the Montreal Convention, but by far the best thing is to file a so-called PIR report right there at the airport at the baggage claims desk.
Practical Summary and Rough Prices
Working out the fees for children can be quite the maths exercise. While traditional airlines take a percentage of your ticket price, low-cost carriers charge a fixed fee for each single leg, even when the child doesn’t have their own seat.
| Fee type / Rule | Ryanair (2026) | Wizz Air (2026) | Full-service airlines (e.g. Lufthansa) |
|---|---|---|---|
| :— | :— | :— | :— |
| Lap infant (0–2 years) | €25 / leg | approx. €27 / leg | 10% of the adult fare |
| Child with own seat (2+ years) | Full adult fare | Full adult fare | Often a child fare (approx. 20–30% discount) |
| Minimum age to accompany a second child | 18 years | 16 years | Usually 16 or 18 (must be verified) |
| Pushchair free of charge | Yes (up to 2 pieces of child equipment) | Yes (for children up to 14) | Yes (often pushchair + car seat) |
If your child turns 2 right during your holiday, you’ll have to buy them a proper seat of their own for the return trip. This is normally handled by splitting the booking or calling the airline’s info line, so keep it in mind when buying your tickets.
Where to Next
If a trip to the airport is coming up and you want everything under control, be sure to check out our other guides too. In them we tackle the most pressing problems parents tend to have before departure.
- Flying with kids: the complete guide
- Travel consent for a child and documents for kids
- Where to sit with a child on a plane
- Taking a pushchair on a plane
- Prague Airport with kids
Frequently Asked Questions
Can I fly alone with two children under two years old?
The standard way doesn’t work. One adult is only allowed to have one child on their lap. For the second child, you must purchase a full seat and bring a certified car seat, or arrange for a second adult as an escort (age varies by airline).
What should I do if my child and I have different surnames?
Definitely bring a copy of your child’s birth certificate. When traveling outside the Schengen Area, it’s also highly advisable to have an officially notarized written consent from the other parent for the trip, to avoid suspicion of abduction.
What are the liquid limits when traveling with a child?
Since October 2025, Terminal 2 (Schengen) has a relaxed limit of up to 2 liters per container. At Terminal 1 (non-Schengen), however, the strict 100 ml limit still applies. Fortunately, baby food and milk have an exemption at both terminals.
Will we be seated together with our children on the plane for free?
The European Union approved a rule in 2026 that children up to 14 years old must be seated with a parent for free. In practice, however, this won’t be fully in effect until mid-2027. Until then, low-cost carriers will seat you together, but often only in the back rows.
Where must an infant on lap be seated on the plane?
For safety reasons, an adult with an infant on lap must always sit in the window seat. This is because two oxygen masks are located there. You cannot sit in the aisle or middle seat.
Do you have to pay for a stroller on the plane?
No, the vast majority of airlines transport children’s strollers for free. You can bring it all the way to the gate, where staff will fold it and place it in the cargo hold. Smartwings, however, requires that the stroller be wrapped in a protective bag, otherwise they won’t acknowledge any damage claims.
Is an infant entitled to compensation for flight delays?
If you’re flying with a child under 2 years old who sits on your lap and doesn’t have their own paid seat, practice is unfortunately inconsistent. ⚠️ Airlines often reject these claims, but it’s always worth filing a claim for the whole family – you have nothing to lose.
Tips and Tricks for Your Vacation
Don’t Overpay for Flights
Search for flights on Kayak. It’s our favorite search engine because it scans the websites of all airlines and always finds the cheapest connection.
Book Your Accommodation Smartly
The best experiences we’ve had when looking for accommodation (from Alaska to Morocco) are with Booking.com, where hotels, apartments, and entire houses are usually the cheapest and most widely available.
Don’t Forget Travel Insurance
Good travel insurance will protect you against illness, accidents, theft, or flight cancellations. We’ve had a few hospital visits abroad, so we know how important it is to have proper insurance arranged.
Where we insure ourselves: SafetyWing (best for everyone) and TrueTraveller (for extra-long trips).
Why don’t we recommend any Czech insurance company? Because they have too many restrictions. They set limits on the number of days abroad, travel insurance via a credit card often requires you to pay medical expenses only with that card, and they frequently limit the number of returns to the Czech Republic.
Find the Best Experiences
Get Your Guide is a huge online marketplace where you can book guided walks, trips, skip-the-line tickets, tours, and much more. We always find some extra fun there!
