Car Rental with a Baby or Child Seat: The Complete Guide

Child safety legislation in Europe requires appropriate restraints for children travelling in cars across all EU and EEA member states. Rental companies provide child seats as paid add-ons, and while this is convenient, the cost over a two-week holiday adds up significantly. This guide covers the seat categories you need to know, what you pay, country-specific rules, and whether bringing your own seat makes more sense.

Child Seat Categories: Group 0 to Group III

European child seats are classified by weight groups under the ECE R44 standard. The newer i-Size standard (ECE R129) classifies by height. Most rental seats comply with one or both standards.

Group 0 and 0+ — Infant Seats

For babies up to 10 kg (Group 0) or 13 kg (Group 0+), which typically covers birth to approximately 12–15 months. These are rear-facing only and often have a carry-handle for use as a car seat and portable baby seat. When installing in a rental car, ensure the front passenger airbag is disabled if fitting a rear-facing seat in the front. Rear seat installation is always recommended.

Group I — Toddler Seats

For children weighing 9–18 kg, roughly ages 9 months to 4 years. These can be forward-facing or rear-facing. Current safety research strongly supports extended rear-facing for as long as the seat allows — this is particularly relevant for Group I when using a rear-facing convertible seat.

Group II — Child Seats

For children weighing 15–25 kg, approximately ages 3–7 years. Usually forward-facing with a five-point harness.

Group III — Booster Seats

For children weighing 22–36 kg, approximately ages 6–12. These are high-backed booster seats that use the vehicle's seat belt rather than a harness. Required until the child is tall enough for the vehicle's belt to fit correctly — EU law generally requires restraints until 135 cm height or 36 kg.

Cost of Renting a Child Seat

Child seat rental is charged per day as an optional add-on. Typical rates in Europe in 2025:

• Infant seat (Group 0/0+): €4–€8 per day
• Toddler/child seat (Group I/II): €5–€10 per day
• Booster seat (Group III): €3–€6 per day

On a 14-day rental, this adds €56–€140 per seat. For two children on a two-week holiday, you could easily pay €200–€250 in child seat rental fees alone. This is a strong argument for bringing your own seats from home or buying new ones specifically for travel.

Cost Comparison: Rent vs Bring Your Own

• Renting an infant seat for 14 days: ~€84–€112
• Buying a budget travel infant seat: €60–€100 new
• Bringing your existing seat: Most airlines allow car seats as free checked baggage — check your airline's policy, but this is common practice

For trips longer than 10 days, buying a new seat and donating or shipping it back is often the same price as renting. For trips shorter than a week, renting is more convenient and similarly priced.

Availability: Book Early and Confirm

Child seats are limited inventory at each rental depot. If a previous renter returns a damaged seat, or a seat has failed an inspection, there may not be a replacement available. Booking a child seat through the aggregator does not guarantee availability in the same way the car is guaranteed.

Best practice: call the rental depot 24–48 hours before your pickup time to confirm the seat is reserved and available. If they cannot confirm, escalate through your booking platform immediately.

Child Seat Regulations in Europe

All EU/EEA countries require appropriate child restraints for children who are under 135–150 cm tall or below the weight threshold for their seat category. Key country-specific notes:

• Lithuania: Children under 12 or shorter than 135 cm must use an approved restraint. Rear-facing seats in the front passenger seat require airbag deactivation.
• Germany: Children under 12 and shorter than 150 cm must use a restraint. This height threshold is higher than most other EU countries.
• France: Children under 10 should use the rear seat. Booster-only (without back) seats are not permitted for children under 15 kg.
• Spain: Children under 135 cm must use a child seat. Children over 135 cm must use the vehicle seat belt.
• Italy: Children under 150 cm or 36 kg must use an approved restraint.
• UK: Children under 12 or shorter than 135 cm must use a child restraint.

Installation: What to Check at Pickup

Whether using a rental company's seat or your own, verify the following at pickup:

• The seat weight range matches your child's current weight — use current weight, not age
• The seat is properly anchored and does not move more than 2 cm side-to-side when tested
• For ISOFIX seats, the connectors are fully engaged (click confirmation)
• Harness straps are routed correctly through the shoulder slots and fit snugly
• For rear-facing seats in the front: the passenger airbag is switched off — verify this physically

Ask the rental agent for help with installation if uncertain. It is far better to take 10 minutes to install correctly than to rush.

Choosing the Right Car Category for Families

With one or two child seats in the back, car category selection matters more for families than for solo travellers. An economy hatchback has limited rear legroom and boot space. Consider:

• One child seat + luggage: Compact or standard category (VW Golf / Ford Focus size) is workable
• Two child seats + luggage: Estate/station wagon or SUV category recommended
• Three child seats: Requires a 7-seat MPV or people carrier — always verify three ISOFIX points or belt positions in the specific vehicle