What is a lie-flat car seat?
A lie-flat car seat, also known as a lie-flat infant car seat or carrycot car seat, is a specialised type of car seat designed to provide a safe and comfortable reclined position for newborns and infants during car journeys. Unlike traditional upright car seats, which keep babies in a semi-upright or upright position, lie-flat car seats allow babies to lie flat on their backs.
This position mimics the recommended sleeping posture for infants and offers several benefits, including better support for your baby's spine and hips, improved breathing and reduced risk of hip dysplasia.
Lie-flat car seats are suitable from birth and are particularly beneficial for longer car rides, where infants can rest comfortably while ensuring their safety during travel.
Is it worth getting a lie-flat car seat?
The decision to invest in a lie-flat car seat depends on various factors, including your baby's age, the duration of your car journeys and your peace of mind. Car seats that enable your baby to sleep flat usually cater for babies up to 75cm or around 12 to 13 months old.
While traditional upright car seats are considered safe and meet legal requirements in the UK, there are essential considerations that might sway your choice in favour of a lie-flat car seat.
Firstly, the two-hour car seat rule is often cited by healthcare professionals and safety experts. It recommends that infants shouldn't remain in an upright car seat for more than two hours at a stretch. This guideline is based on concerns about potential breathing and comfort issues that can arise when babies are seated in a semi-upright position for extended periods.
In 2016, a study took place at the Great Western Hospitals NHS Foundation Trust with additional support from the University of Bristol. This research team looked into how car journeys affect infants. What they found was that little ones born prematurely or at a tender age might be at risk of some breathing difficulties if they're seated upright in car seats at a 40-degree angle for long stretches.
Lie-flat car seats address this concern by allowing your baby to recline in a more natural, comfortable sleeping posture. This position helps keep their airways clear and supports the proper alignment of their spine and hips. Additionally, lie-flat car seats are particularly beneficial for longer journeys, as they enable your baby to nap and rest comfortably while ensuring their safety during travel.
Ultimately, whether you need a lie-flat car seat depends on your specific circumstances. If you go on extended car trips with your newborn or prefer the added reassurance of a more natural sleeping position, a lie-flat car seat could be a valuable investment. However, for shorter journeys, a traditional upright car seat that complies with safety regulations may suffice.
What age do babies not need to lie flat?
Babies typically no longer need to lie flat in a fully reclined position when they can sit up independently, which typically occurs between five and seven months of age.
However, it's important to note that the exact timing can vary from one baby to another, so it's essential to observe your baby's developmental milestones and consult with your paediatrician for guidance on when it's safe to transition to a more upright position in a lightweight stroller or car seat. The transition should be gradual and based on your baby's individual readiness.
When it comes to the safest sleeping position for newborns, the NHS, says it’s best for babies to sleep flat on their backs for the first six months, or until they can sit up on their own.
What is i-Size?
According to the NHS, i-Size is a European car seat safety standard under ECE R129 that aims to replace the older R44/04 regulation with stricter safety standards in time. However, currently both are available to buy and legal to use in the UK.
Some key features that make a car seat i-Size compliant include:
Rear-facing installation: i-Size car seats in the 0+ category are typically installed in a rear-facing position, which is considered safer for infants and young children.
ISOFIX compatibility: i-Size car seats require ISOFIX connectors, which provide a secure and standardised attachment to the car's chassis, reducing the risk of installation errors.
Side-impact protection: i-Size car seats have enhanced side-impact protection to minimise injury risk in side collisions.
Height-based sizing: i-Size seats are categorised based on your child's height rather than weight, ensuring a better fit and improved safety as your child grows.
Top tether or load leg: Many i-Size car seats include a top tether or support leg for added stability and safety.
Standardised testing: i-Size seats undergo rigorous standardised testing to meet safety criteria, including crash tests and performance assessments.
Universal compatibility: i-Size seats are designed to fit in all i-Size-approved vehicles, enhancing compatibility across different car models.
Easier installation: The standardised design of i-Size seats and ISOFIX connectors simplifies the installation process, reducing the risk of errors.
What are the differences between R44 and R129 car seats?
As detailed in our best toddler car seats guide, i-Size seats will replace all R44 seats in time. But at the moment, here are the key differences between them:
R44
Classification is based on weight
While side-impact tests aren’t mandatory, certain manufacturers still choose to conduct them
Testing for frontal collisions is performed at a velocity of 50km/h, while rear-impact collision tests are carried out at 30km/h
The seat can be installed using either a seat belt or ISOFIX connectors
The seat must remain rear-facing until the child reaches 9kg (approximately nine months of age)
R129 (i-Size)
Categorisation relies on height measurements
Side-impact evaluations are compulsory
Only ISOFIX installation is allowed
The seat should remain rear facing until the child is around 15 months
All seats have side-impact protection, which typically involves cushioning around the headrest and sides to absorb impact forces during a car accident, thus preventing severe head injuries
Read next: Maxi-Cosi Nomad Plus foldable travel car seat review
How to choose the best lie-flat car seat
When selecting the best lie-flat car seat for your baby, consider the following factors:
Safety first: Make sure the car seat meets the latest safety regulations, like the R44 and/or i-Size standard (ECE R129) and has undergone thorough crash testing.
Age and weight suitability: Check if the car seat is suitable for your child's age and weight. Some lie-flat seats work from birth, while others have varying weight limits.
Easy installation: Ensure the car seat can be easily and securely installed in your vehicle. Some use ISOFIX connectors, while others, like the britax römer BABY-SAFE PRO uses both the ISOFIX and/or seat belts.
Flexible recline: A good lie-flat car seat should typically recline to an angle of between 130 to 180 degree or as close to flat as possible. This position allows for a safe and comfortable sleeping posture for newborns and young infants while travelling in the car.
Side-impact protection: For added safety, consider seats with enhanced side-impact protection, like reinforced sides or impact-absorbing materials.
Vehicle compatibility: Check if the car seat fits well in your specific vehicle, especially if you have a unique car model and more than one car seat to fit in the back.
User-friendly features: Look for a car seat with convenient features like an adjustable harness, one-handed recline adjustment and simple installation instructions.
Weight and portability: Consider the seat's weight as you might need to carry it when your baby isn't in the car. Lightweight options like the Cybex Cloud Z2 i-Size can be more practical.
Travel system ready: If you plan to use your lie-flat car seat with a stroller or pram, confirm its compatibility with your chosen system. Most of the lie-flat car seats on our list come with a range of travel system options.
The padding: Assess the lie-flat car seat's padding and overall comfort to ensure your baby is well supported.
Easy to clean: Check if the lie-flat car seat’s covers and padding are removable and machine washable for hassle-free maintenance.
Budget-friendly choices: It’s always a good idea to determine your budget and explore options within your price range, keeping safety and quality in mind.
Trusted brands: Consider reputable brands known for their dedication to safety and high-quality products when making your decision. Luckily, all the lie-flat options on our list are made according to the highest safety standards.
How much should I spend on a lie-flat car seat?
The price range for lie-flat car seats can vary significantly depending on the brand, features and quality. Generally, you can find lie-flat car seats ranging from £150 to £400 or even higher for premium models. The amount you should spend on a lie-flat car seat depends on your specific needs, preferences and budget.
When choosing which one to buy, it’s wise not to compromise on the safety features, but do think about how long you plan to use the car seat. For instance, some lie-flat car seats like the Cybex Cloud Z2 i-Size are suitable from birth to a higher weight/age limit, potentially providing a longer useful life.
Can you use a secondhand lie-flat car seat?
As the NHS and car seat safety expert, Jan James, from Good Egg Car Safety advises, it’s best to avoid purchasing secondhand lie-flat car seats as they might be damaged, missing parts, lack instructions and could be incompatible with your car.
About the author
Tammy Jacks has 15+ years' experience in the publishing industry, enjoying a long and fruitful career as Managing Editor and Health & Beauty Editor for Woman & Home magazine in South Africa. She later went on to become Assistant Editor of the popular South African parenting title Living and Loving, and has written for numerous lifestyle publications including Oprah Mag SA, Health Intelligence, Your Family Magazine, Longevity, and pharmaceutical company Clicks Clubcard Magazine, as well as edited books for popular fitness influencers and health professionals.
Tammy is a distinguished researcher and writer in the field of child safety, with a notable focus on the critical domain of car seats. Her extensive expertise and commitment to child safety have made her a trusted authority in providing comprehensive insights and guidance to parents and caregivers looking for the right car seat for their children. As a mum to an eight-year-old, Tammy has personally tried and tested numerous car seats over the years, across all age categories.
About the editor
Laura Westerman is an editor, writer and Deputy Head of Editorial Content at Mumsnet. With over seven years' experience as a full-time editor, five of which have been spent writing, commissioning and editing car seat product reviews and round-ups, Laura has a keen eye for what parents love and likes nothing more than putting together honest reviews to make parents' lives that little bit easier.
In addition to her work as a writer and editor, she has also appeared in a number of baby product review videos for Mumsnet's YouTube channel. She is mum to a one-year-old.
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