This listing is pending verification: the Amazon link may point to a different variant than the one we researched. Check the listing before buying.
Britax Poplar S
Doona
Britax safety heritage in a slim convertible that fits three across and travels better than most full-size seats. The Britax Poplar S car seat is the pick parents are talking about this season.
About $550
See it on Amazon- ✓ Checkout and returns handled by Amazon
- ✓ Estimated price as of 2026-10-05
- ✓ ASIN B0BWH9C31X
Specifications
- Seat width
- Check listing
- Seat weight
- Check listing
- Rear-facing and forward-facing limits
- Check listing
- FAA approval label
- Check listing
- Installation system
- Check listing
Pros
- Slim footprint solves the three-across rental problem
- Strong brand reputation for safety and build
- Works as a home seat, not just a travel one
Cons
- Does not fold or convert to a stroller; still a full seat to carry
- Research recommended the Doona; verify the listing
Ideal for
Best for
Families with two or more young kids who rent midsize cars on trips.
Skip it if
Parents of a single infant who want a car-seat-and-stroller combo like the Doona.
Why we recommend it
Choose the Britax Poplar S when you have multiple kids and need the slimmest full-featured convertible of the four, accepting that it weighs more than the folding WAYB Pico.
Last updated: 2026-10-10
Why it is our Trending Pick
Parents who want a safety-first brand and a narrow footprint should put the Britax Poplar S car seat on the shortlist. It is for families with infants through preschoolers who need a seat that fits beside siblings in a rental, carries through an airport and is reassuring enough to be the everyday seat at home.
It holds the Trending slot in our car seats for flying roundup. Our research recommended the Doona Infant Car Seat & Stroller for its car-seat-plus-stroller wow factor; the Amazon link sells the Britax Poplar S, so this page describes the Britax and flags the swap for verification. The Britax Poplar S car seat earns attention on its own terms: a slim convertible from a brand with a long safety reputation, designed so three seats can share a back seat. For traveling families that narrow profile is what makes rental cars and rideshares workable.
A typical trip looks like this: the seat goes in a padded travel bag and gets checked free at the counter, or rides on a cart to the gate. At the destination it installs rear-facing or forward-facing in the rental, and because it is narrow, two kids and an adult can fit in the back row of a midsize car. On long drives the padding and recline feel closer to a home seat than a travel seat.
The drawback is that it is not a folding travel seat and does not convert into a stroller the way the Doona does; it is a convertible you carry, with the weight that implies. Skip it if you want the lightest option or an infant-only travel system. Check the Amazon listing for current weight limits, width, seat weight and FAA approval.
Compare with the other car seats for flying picks
Frequently asked questions
Straight answers to what travelers ask most about britax poplar s.
Is the Britax Poplar S approved for use on airplanes?
Britax convertible seats commonly carry FAA approval for harnessed use on aircraft, but you need to confirm the label on the seat and the statement on the Amazon listing. Also check width against your airline's aircraft seat dimensions.
How does the Britax Poplar S differ from the Doona?
The Doona is an infant car seat with built-in stroller wheels, used from birth until the infant limit. The Poplar S is a convertible that lasts through preschool but does not roll. Choose based on your child's age and how long you want the seat to last.
Does the Britax Poplar S fit three across?
It is designed with a slim profile to make three-across configurations possible, but success depends on the vehicle and the other seats involved. Check the width on the Amazon listing and the rental car's back seat width before relying on it.
Britax Poplar S
As an Amazon Associate, PickQuickWay earns from qualifying purchases. Prices and availability are accurate as of the date shown and are subject to change.