We’ve noticed that many of the families we help in our Facebook group are looking for car seats to fit their vehicles rather than shopping for a new vehicle. We’ve also noticed a terrific trend – narrow car seats that offer families more options in tight spaces. Britax joins this important club with the Poplar, a narrow convertible car seat that reminds us of Call the Midwife every time we say the name.
CSFTL Quick Stats
- Rear facing weight range: 5-50 pounds
- Rear facing height range: no minimum height – 49 inches. The seat is outgrown rear facing when the child’s head is less than 1 inch from the top of the headrest
- Forward facing weight range: 22 – 65 pounds
- Forward facing height range: 28 – 49 inches tall and the tops of the child’s ears are at or below the top of the headrest
- Forward facing age minimum: Britax recommends that children ride rear facing until a rear facing height or weight limit is met
- Lower anchor weight limit: 35 pounds
- Follows NHTSA guidelines for crash replacement
- Allows 3 inches of overhang on the vehicle seat in both rear facing and forward facing modes
- Recline positions: 6 – No restrictions beyond using the position that installs the seat the correct angle rear facing or forward facing
- Expiration: 10 years
- It is narrow
- ClickTight lockoff installation
- No rethread harness
- Optional/removable cup holders
- Highest harness position: 17 inches
- Lowest harness position without insert: 9 inches
- Lowest harness position with insert: 7 inches
- Width at widest point: 17 inches at the headrest
- Width at cupholders without cup holders installed: 16.5 inches
- Width with cupholders installed: 20 inches
- Width of base: 13.5 inches
- Seat weight: 26 pounds
- Front-to-back measurement: 28 inches on flat ground in the most reclined position (This will vary in/by vehicle)
- Crotch buckle positions: 4, 5.5, and 7 inches from the back of the seat pan without insert
Inserts and Harness Pads
Normally we don’t have a section for padding but the Poplar has a lot of rules around the harness pads so we wanted to highlight them.
- Infant insert required until the child weighs 22 pounds
- Harness pads are permanently secured to headrest but can be stored for infants under 22 pounds when rear facing
- Harness pads required rear facing when the child weighs between 22-50 pounds
- Harness pads required forward facing when the child weighs between 22- 65 pounds for vehicle lap/shoulder belt or lower anchor installation
- Harness pads must be stored 22-25 pounds for forward facing vehicle lap belt only installation.
Since the Poplar’s most prominent selling feature is being narrow, we attempted to install it in as many three across/two side by side situations as possible. This experiment included a visit to a local car dealer, where many “helpful” sales associates tried to instruct us about car seats and car seat installations. Thanks again, kind sirs. Very helpful.
We had the most success with installing the Poplar next to other narrow car seats and booster seats that tend to work in 3 across scenarios like the Chicco MyFit, Clek Fllo, and Graco RightGuide seat belt trainer but also attempted wider seats like the Britax Grow With You ClickTight and the Maxi-Cosi RodiSport booster seat.
When installing 2 car seats side by side, sometimes pulling a seat closer to the door is necessary in order to create enough width to fit all of the car seats. Having a car seat with a lockoff can help to secure that seat slightly off center.
Vehicles We Tried
I attempted rear facing and forward facing installs in a 2023 Subaru Crosstrek, 2017 Toyota Sienna, 2020 Toyota Highlander, 2015 Ford Explorer, 2017 Ford Fiesta ST, 2023 Toyota Sequoia, 2021 Volvo V90 XC, 2022 Honda Accord, and a 2024 Honda Odyssey.
As a disclaimer – we don’t usually try out this many vehicles. I happened to have these available at different points during the review so I took advantage and tested the seat out. The Poplar consistently installed well in rear facing mode in nearly every seating position. Equally as consistent was the need to remove the vehicle headrests for forward facing installs to prevent headrest interference.
3 Across with Wider Car Seats
We installed the Poplar next to a Britax Grow with You and the Maxi-Cosi Rodisport high back booster in the Toyota highlander and a range of 2 side by side or 3 across in the Odyssey.
I found the best setup involved installing the Poplar on a full-sized outboard vehicle seat rather than on a slimmer middle seat, though we did find that the Poplar worked in some center seating positions that were on the wider side.
Side Note about the Sienna/Odyssey Middle Seat
The dealership had a 2017 Toyota Sienna, which has a tiny vehicle seat in the middle of the second row. This seating position is challenging on the best of days so we weren’t really expecting the Poplar to fit there. Surprise! I wasn’t able to get it installed there.
Even with the Poplar’s narrow base, it was no match for the tiny seating position.
The Honda Odyssey has a slightly larger second row center seat. In one corner, the base of the Poplar partially hung over the side of the vehicle seat. While the manual does state no side overhang, we encourage families with small seating positions such as this one to reach out to Britax directly for clarification on whether or not their particular situation is permitted.
I did find that this seat was extremely compact when in the most upright position in rear facing mode. This will be nice for families who have smaller back seats or who have older siblings that need to scurry under their rear facing sibling’s car seat on the way to their seating position.
The seat includes some rather large harness pads that remain attached to the seat even when they’re not in use. While on one hand, we applaud things that prevent caregivers from losing car seat parts, we struggled a bit with storing these pads properly. We reached out to Britax during the review process and were pleasantly surprised when they tagged us in this handy video that shows how to store them.
Recline Angle Indicator
In the manual that came with our seat, there is a photo designating the “maximum recline position” which is actually the most upright, not most reclined. Britax has confirmed that any recline position within the blue zone on the indicator is safe for rear facing mode. The section has been removed from the online manual and you can request an updated copy from Britax. We encourage caregivers to confirm that they have the latest version of the manual.
We applaud Britax for updating the manual so quickly.
Similarly to some of the other convertible car seats in Britax’s lineup, the Poplar also features their ClickTight installation system. This system includes an easy-to-open panel and some clearly marked belt paths — blue for rear facing and green for forward facing. Just open the panel, thread the vehicle seat belt through the exposed belt path, remove most of the slack from the belt, then close the panel. Don’t forget the top tether for forward facing installations.
Before installing the seat, it needs to be in the right recline position for the child who will be riding in the seat. Use any of the 6 recline positions as needed to set the proper recline angle for the child. All 6 positions can be used in either rear facing or forward facing mode, though obviously not at the same time. Here we see the Poplar installed at the most upright recline angle.
Recline Angle for Newborns
The manual allows for the use of a rolled towel if needed to install the seat at the correct recline angle rear facing. For infants who do not have good head and neck control, we found that we needed to fully recline the seat using the seat’s recline adjuster and add a rolled towel underneath the front of the base. This configuration moved the ball in the recline angle indicator into the right position for a newborn.
Installation: Rear Facing
Britax recommends that the Poplar be installed with the vehicle seat belt so we did that first.
Vehicle Seat Belt
To install the Poplar rear facing with the vehicle seat belt, place the car seat on the vehicle seat with the harness facing the back of the vehicle seat. Adjust the recline angle as needed for the age of the child and to account for the vehicle seat’s shape, then open the ClickTight panel. Take a moment to identify the rear facing belt path.
Route the vehicle belt through the rear facing belt path and buckle. Remove the slack and then close the ClickTight panel.
For this seat, I found the ClickTight panel needed a little bit more force to close than I’m used to. I found it was easiest to push down firmly right on top of the release button area.
Check for movement by using the force of a firm handshake with your non-dominant hand at the rear facing belt path. It should not move more than an inch side to side/front to back.
Rear Facing: Lower Anchors
Britax recommends families install the Poplar with the vehicle seat belt. We’re installing it with the lower anchors for your reference but if we were working with a caregiver, we’d follow the instructions and try the vehicle seat belt first.
Remove the lower anchors from their storage location on the car seat. The lower anchors are nicely tucked away in the back/bottom of the base. They’re easy to access and store when not in use.
Place the car seat on the vehicle seat with the harness facing the vehicle’s seat back, adjust the recline angle as needed for the age of the child, then open the ClickTight panel. Take a moment to identify the rear facing belt path.
Route the lower anchor connectors through the rear facing belt path and attach to the vehicle lower anchors. Remove the slack, being careful not to overtighten and then close the ClickTight panel.
Check for movement by using the force of a firm handshake with your non-dominant hand at the rear facing belt path. It should not move more than an inch side to side and front to back.
Forward Facing Installation Challenges
We want to preface this section by highlighting some challenges we had while installing the seat in forward facing mode. The vehicle headrest interfered with a secure installation every vehicle I tested. In one car that had a very deep vehicle seat seat, I couldn’t raise the headrest beyond the car seat’s shell. This challenge made it pretty unlikely that the Poplar would work well for a forward facing installation in that particular vehicle. This is not a seat we’d recommend for a family with fixed/protruding/non removable headrests. Please take a moment to examine your vehicle’s headrests before moving forward with a buying decision that includes the Poplar.
Headrest Interference Examples
Here is a brief medley of the challenges we faced when installing the Poplar forward facing in a few different vehicles with fixed headrests.
Forward Facing: Vehicle Seat Belt
Place the car seat on the vehicle seat, adjust the recline to the desired level, put the top tether over the headrest and open the ClickTight panel. Even though any recline angle position can be used in forward facing mode, I found the installation was most secure using the most upright setting.
Take a moment to identify the forward facing belt path. Route the vehicle seatbelt through the forward facing belt path, buckle, remove any slack, and close the ClickTight panel. Attach and tighten the top tether per the manual’s instructions.
Check for movement by using the force of a firm handshake with your non-dominant hand at the forward facing belt path. The car seat should not move more than an inch side to side or front to back.
Forward Facing: Lower Anchors
Remove the lower anchors from their storage location on the car seat. Place the car seat on the vehicle seat and adjust the recline angle as needed and open the ClickTight panel. Take a moment to identify the forward facing belt path.
Route the lower anchor connectors through the forward facing belt path and attach to the vehicle lower anchors. Remove the slack, being careful not to overtighten and then close the ClickTight panel.
Check for movement by using the force of a firm handshake with your non-dominant hand at the forward facing belt path. It should not move more than an inch side to side/front to back.
The top tether is a crucial part of your child’s car seat. It reduces the risk of head excursion by 4-6 inches in a crash. Britax uses a V-shaped tether that works a little differently than the single strap most other manufacturers use — it usually needs to be routed around the vehicle headrest.
Fit to Child
Our huggable images doll is 7 pounds and 17 inches and fits very well both with and without the harness pads. To allow the chest clip to be at armpit level, I pushed the harness pads into the harness opening per Britax’s recommendation. This gave us about an extra ½ inch to work with.
In order to get the doll properly positioned, I needed to sit it on top of the bulky part of the required insert. I look forward to seeing this insert used with human infants and how it affects their fit as they approach the limit. I am inclined to think it’ll be snug based on the thickness of the insert.
16 Month Old Doll
Our 16 month old doll is practically weightless and is 31 inches tall. This model has quite a bit of room to grow in this seat.
3 Year Old Child
This 3.5 year model weighs 35 pounds and is 38 inches tall. She fits well in this car seat in rear facing mode. She described it as comfortable and had no issues falling asleep promptly on her first ride. She did, however, ask why I have so many car seats :).
Because this seat is so compact front-to-back, something we celebrate in certain situations, there isn’t a lot of extra legroom. The lack of legroom presented no challenges for this long-legged toddler. I did find that I had to adjust the harness strap height to ensure that the straps were both slightly below her shoulders AND she had one inch of headrest above her head. The requirement to have one inch of headrest above the child’s head may be problematic for children with longer torsos or larger heads.
3 Year Old Child
This same toddler remains 35 pounds and is 38 inches tall. She fit beautifully in the seat in forward facing mode as well with quite a bit of room left to grow. Since this seat has a deeper forward facing recline and she has never ridden forward facing, I found myself needing to teach her that she couldn’t put her legs up on the seat in front of her nearly instantly. She would benefit from a lightweight footrest but someone younger or with shorter legs may not be able to utilize this trick to help keep their legs down.
Important Information: Where to Find
Manual storage: the manual stores behind the cover in a little pocket or some type of designated space.
Date of manufacture label: the Poplar expires 10 years after the date of manufacture. The label can be found on the back of the car seat to the left of the top tether storage.
FAA Approval: this seat is approved for use on aircraft. For both rear and forward facing, the ClickTight panel remains closed when the seat is installed on an airplane seat. Rear facing, the airplane seat belt goes over the cover, through the rear facing belt path.
Forward facing, the airplane seat belt goes under the cover through the forward facing belt path.
The Poplar is a solid addition to Britax’s lineup. The seat really shines in rear facing mode. It’s extremely compact when rear facing in the most upright position, it’s narrow side to side and includes the ClickTight installation system for simple installation.
The Poplar’s biggest selling point is that it’s compact in rear facing mode, narrow, and easy to install. Those are not small things. However, it’s not the longest-lasting option for extended rear facing, nor does it offer a ton of legroom. I found it to be a curvier narrow seat which presented issues in the small center seating positions and in smaller cars where the goal was to put another car seat beside it. Because of this, I found it worked best on full sized outboard seats, next to other narrow seats, next to low profile boosters, or in between two boosterless riders.
Needing to be able to remove the vehicle headrest to allow the seat to be used in forward facing mode was limiting, so it’s not a slam dunk for every situation — no single car seat is — but we’d definitely suggest the Poplar for families who need a compact AND narrow rear facing option.