Britax Poplar S

Rear-facing: 5-50 lbs. | 49″ or less
Forward-facing: 30-65 lbs. | 49″ or less

Pros:
  • Very narrow; great for 3-across
  • Compact front-to-back when more upright
  • Robust ClickTight belt-tensioning lockoff system
Cons:
  • Not compatible with vehicle head rests that angle forward
  • Permanently attached harness pads that must be used starting at 22 lbs.
  • Thick infant cushion that must be used until 22 lbs.
More info

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Specifications

Rear-Facing

Weight limits: 5-50 lbs.
Height limits: 49″ or less and head must be 1” below top of head rest

Forward-Facing

Weight limits: 30-65 lbs.
Height limits: 49″ or less
Age limits: After reaching RF weight and height limits

A lockoff is a built-in feature that locks your seat belt for you. When a lockoff is present, you will not need to engage the locking mechanism of the seat belt.

A belt tensioner tightens the seat belt for you with little effort; it uses leverage to make the job easier. It presses the belt into a channel(s) to shorten it mechanically and create the tension.

load leg

A load leg rests on the floor of the vehicle and manages crash energy to reduce head injury in rear-facing carseats. It’s available on 2 convertible models. Not all vehicles allow load legs.

Poplar S ARB

An anti-rebound bar (ARB) is an energy management feature that helps stabilize a rear-facing carseat and stops it from pivoting around its belt path. ARBs can be found on rear-facing only infant seats and on convertible/all-in-one seats.

Widest point: 17”
Highest harness height: 18″

Installation/Vehicle Info

Lockoff: Yes
Belt-tensioner for easy install: Yes

Load leg: No
Anti-rebound bar: Yes

Manufacturer’s preferred method of installation: Seat belt

CarSeatSite notes on installation: Try installing this seat forward-facing first before your return window is closed. The Poplar/Poplar S is incompatible with vehicles that have head rests that protrude forward. If you can remove them, you will need to do so before installing this seat forward-facing.

Vehicle seat protectors: Not allowed

Flame retardant free covers available: Yes

FAA approved: Yes

Crash replacement guidelines: After a moderate to severe crash following NHTSA guidelines

Fit to Child

Harness type: No-rethread

Inserts: Lower infant insert (required 5-22 lbs.; must remove at 22 lbs.), upper body support pillow (optional 5-20 lbs.), permanently attached harness pads (may be used under 22 lbs.; must be used 22-65 lbs. RF/FF), and a head pad (optional)

Newborn fit: Iffy

Lifespan/expiration: 10 years

Comments
The Poplar S and its sibling, the Poplar, is a great seat for 3-across because it’s narrow and has the ClickTight belt-tensioning lockoff panel, which does the hard work for you. The base is on the wider side, though, which may make it more difficult to fit between narrow seat belt anchors. The lower infant insert is thick and cushiony, which is comfortable, but it’s required until 22 lbs., which does affect fit on some children.