Britax Poplar S Convertible Car Seat, 2-in-1 Car vs Maxi-Cosi Romi 2-in-1 Convertible Car Seat, Infant
Updated August 2026 — Britax Poplar S Convertible Car Seat, 2-in-1 Car leads on weight and harness.
The Britax Poplar S offers superior safety and comfort features, while the Maxi-Cosi Romi excels in portability and affordability.
Why Britax Poplar S Convertible Car Seat, 2-in-1 Car is better
Safety Features
Includes advanced safety technologies like SafeCell crumple zone.
Comfort
Premium padding and adjustable harness for better fit.
Installation
ClickTight technology simplifies installation.
Why Maxi-Cosi Romi 2-in-1 Convertible Car Seat, Infant is better
Price
Significantly cheaper at $149.99.
Weight
Weighs just over 9 lbs, making it very portable.
Eco-Friendly
Made with 100% recycled EcoCare fabric.
Overall score
Specifications
| Spec | Britax Poplar S Convertible Car Seat, 2-in-1 Car | Maxi-Cosi Romi 2-in-1 Convertible Car Seat, Infant |
|---|---|---|
| Max Weight | 65 lbs | 50 lbs |
| Rear-Facing | 50 lbs | 40 lbs |
| Forward-Facing | 65 lbs | 50 lbs |
| Fabric | Flame-Retardant | EcoCare |
| Machine Washable | Yes | Yes |
Dimension comparison
Overview of the Britax Poplar S Convertible Car Seat
The Britax Poplar S Convertible Car Seat is a highly regarded option in the convertible car seat market, priced at $399.99. It boasts a bestseller rank of 5,239, indicating solid sales performance. This car seat is designed with the safety and comfort of children in mind, accommodating up to 50 lbs when installed rear-facing and easily transitioning to a forward-facing position for children up to 65 lbs. Its ClickTight installation technology simplifies the setup process, making it user-friendly for parents.
The Poplar S features a 17-inch SpaceSaver design that allows for three-across installations in most vehicles, although Britax does note that fitment can vary. Additionally, its carbon steel frame and SafeCell crumple zone enhance crash protection, making it a reliable choice for safety-conscious parents. Overall, this car seat combines functionality with premium comfort, making it a strong contender in the convertible car seat category.
Overview of the Maxi-Cosi Romi 2-in-1 Convertible Car Seat
The Maxi-Cosi Romi 2-in-1 Convertible Car Seat offers a lightweight alternative at a significantly lower price of $149.99, making it about 62% cheaper than the Britax Poplar S. It ranks 9,637 in sales, which is decent but indicates less popularity compared to its competitor. Designed for children weighing between 5-40 lbs in rear-facing mode and 30-50 lbs in forward-facing mode, the Romi is versatile for growing families.
One of its standout features is the EcoCare fabric, made from 100% recycled materials, promoting environmental sustainability. The Romi is also exceptionally lightweight at just over 9 lbs, making it one of the lightest convertible car seats available, which is ideal for families on the go. Combined with its machine-washable fabrics and easy installation, the Romi is a practical choice for parents seeking convenience and value.
Safety Features Comparison
In terms of safety features, the Britax Poplar S Convertible Car Seat is equipped with a patented SafeCell crumple zone and a V-shaped tether that helps manage crash energy, enhancing its safety profile. The carbon steel frame adds further security, minimizing movement in the event of a crash. The Poplar S is designed to allow children to ride rear-facing longer, which is recommended for improved safety.
On the other hand, the Maxi-Cosi Romi meets federal safety standards and is designed with a focus on lightweight portability. While it does not have the same extensive safety features as the Britax, it is still engineered to provide adequate protection for children. The Romi’s design includes an adjustable head pillow for added support, but it lacks some of the advanced safety technologies found in the Britax Poplar S. Thus, while both seats are safe, the Britax offers more robust safety features.
Comfort and Convenience
The Britax Poplar S emphasizes refined comfort, featuring premium inserts and padding that enhance the seating experience for children. Its 14-position no-rethread harness and headrest adjust together, making it easier to achieve a perfect fit as your child grows. Additionally, the car seat cover is machine washable and dryer safe, ensuring easy maintenance.
In contrast, the Maxi-Cosi Romi prioritizes convenience with its ultra-soft PureCosi fabrics, which are also machine washable. The Romi's lightweight design makes it easy to transfer between vehicles, and the top tether doubles as a hands-free carrying strap. While it provides comfort, it may not match the premium feel of the Britax Poplar S. Parents must evaluate whether they prioritize comfort or convenience in their choice of car seat.
Portability and Travel
Portability is a key strength of the Maxi-Cosi Romi. At just over 9 lbs, it is one of the lightest convertible car seats available, making it ideal for travel or quick transfers between vehicles. Its design allows it to be comfortably carried using the innovative top tether strap, making it easy for parents on the move.
In comparison, the Britax Poplar S is heavier and more robust, weighing significantly more than the Romi. While it is designed for stability and safety, its weight may pose a challenge for parents frequently moving the seat. For families who travel often or need to switch between cars regularly, the Romi's lightweight design could be a decisive factor.
Installation Ease
The Britax Poplar S features ClickTight installation technology, which simplifies the process by allowing parents to easily open, thread, buckle, and click the seat closed without guesswork. This user-friendly feature can significantly reduce the stress associated with car seat installation.
Conversely, the Maxi-Cosi Romi includes a one-click LATCH system that enables quick and easy installation, although it may not be as intuitive as the ClickTight system. Both car seats are designed for straightforward setup, but the Britax Poplar S stands out for its ease of use, especially for those who may struggle with traditional installation methods.
Price Comparison
The Britax Poplar S is priced at $399.99, positioning it as a premium option in the convertible car seat market. In contrast, the Maxi-Cosi Romi is competitively priced at $149.99, making it a more budget-friendly choice. This represents a price difference of about $250, which may be a significant factor for many families. While the Britax offers advanced safety features and comfort, the Romi's affordability allows parents to meet their needs without breaking the bank.
Which should you buy?
In summary, the choice between the Britax Poplar S Convertible Car Seat and the Maxi-Cosi Romi 2-in-1 Convertible Car Seat ultimately depends on your family's specific needs. The Britax Poplar S excels in safety, comfort, and ease of installation, making it an excellent choice for those who prioritize these features and can accommodate the higher price. On the other hand, the Maxi-Cosi Romi offers exceptional portability and affordability, making it ideal for families seeking a lightweight, budget-friendly option. Each car seat has its strengths, so consider your priorities when making your decision.

