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Britax Willow Infant Car Seat with Aspen Base

An infant car seat with one mode: rear-facing infant 4 to 30 lb, 17 to 32 in.

At a glance

Fits children from 4 to 30 lb
Up to 32 in tall
Rear-facing infant only
Anti-rebound protection
Seat weighs 8.99 lb
6-year usable life
Certified for aircraft use

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Britax product page Manual

Specifications checked against Britax’s US site and manual on September 17, 2026. Not hands-on tested. How I research

Who is the Willow Infant Car Seat with Aspen Base for?

The Britax Willow is a rear-facing infant seat sold with the Aspen ClickTight base in the Willow Brook travel system. It fits babies 4 to 30 lb and 17 to 32 in, with the top of the head at least 1 in below the top of the shell. It installs with or without the base and expires after 6 years.

Reasons to consider it

An Aspen ClickTight base whose indicator is all black with no red pins when closed correctly
Inner harness loop and hip slots for babies up to 11 lb, with outer positions to 30 lb
Certified for aircraft, using a baseless lap belt installation
A listed 21" seat back height and 10" shoulder width

Things to weigh up

Britax's US site sells it only inside the Willow Brook travel system
A lap-only belt must be locked; without the base, a locking clip is needed if the belt cannot lock
Britax lists the Aspen base at 9.09 lb
Expires 6 years after manufacture

My take on the Willow Infant Car Seat with Aspen Base

It suits parents buying the Willow Brook travel system who want a ClickTight base that clamps the vehicle belt and shows a clear indicator. Britax lists adjustment points at the hips, the shoulders and between the legs, which help with fitting a small baby. Compared with the Arbor, the limits are the same; Britax lists the Willow at 8.99 lb with a 9.09 lb base, against 9.9 lb and 7.4 lb for the Arbor and its StayTight base.

A research summary of Britax’s published specifications and manual, read October 7, 2026. Not a hands-on test or a crash-safety rating.

Who the Willow Infant Car Seat with Aspen Base fits

This seat covers one stage. Britax gives it a 6-year life from the date of manufacture, so check the date label before using a hand-me-down.

Rear-facing infant4 to 30 lb · 17 to 32 in: The child faces the back of the car, which keeps the head, neck and spine supported in a frontal crash. Keep this mode as long as the child fits it.

A parent lifting a newborn beside an empty rear-facing infant car seat

What are the Willow Infant Car Seat with Aspen Base weight, height and age limits?

Britax Willow Infant Car Seat with Aspen Base limits by mode
Mode	Child weight	Child height	Minimum age	Conditions
Rear-facing infant	4 to 30 lb	17 to 32 in	Not published	Product page states height 'Less than 32 in'; 17-32 in from manual

A child must meet every limit for the mode they use. The labels on your seat and its manual are the final word.

Willow Infant Car Seat with Aspen Base specifications

Seat weight: 8.99 lb
Width: Not published
Usable life: 6 years
Aircraft use: Certified for aircraft (see manual for which modes)
Base weight: 9.09 lb
Harness slot heights: 5.5, 7.5, 9.5, 11.5 in
Buckle strap depths: 2.25, 5.5 in
Seat area depth: 12 in
Seat area width: 9.5 in
Shoulder width: 10 in
Seat back height: 21 in
Included base: Aspen base

How the Willow Infant Car Seat with Aspen Base installs

Belt lock-off: ClickTight installation. A lock-off clamps the vehicle belt so you do not have to switch the belt's retractor into its locked mode.
Lower anchors: Quick-push LATCH connectors. Check your vehicle manual for which seating positions have anchors, and switch to the seat belt once the child passes the anchor weight limit in the manual.

Every install is a fit between one seat and one vehicle. Read both manuals, and use a free inspection station if anything is unclear.

An empty car seat installed on a back seat, seen through an open car door

Will it fit your car?

Britax does not publish a width for this seat, so measure your back seat and compare it with the seat in a store before buying. It weighs 8.99 lb, which matters if you will move it between cars or carry it through an airport.

Check your vehicle manual for lower anchor positions and any head-restraint rules.
Rear-facing seats need front-seat room: try the install behind the driver before you commit.
Certified for aircraft use, so it can travel as a seat rather than checked baggage.

What features does the Willow Infant Car Seat with Aspen Base have?

ClickTight installation
ReboundReduce carry handle (stability bar when upright)
Quick-push LATCH connectors
Baseless installation
Side impact tested
UPF 50+ canopy

Colors listed in the US

Graphite Glacier, Navy Glacier, Onyx Glacier.

What to know before you live with it

Installing the Aspen base with ClickTight

Press the recline button and move the base until the whole blue marker shows between the two lines. Open ClickTight, lay the lap and shoulder belt across the base, tuck it under ClickTight and both belt guides, buckle, remove slack and push ClickTight closed until the window is entirely black with no red pins. Do not lock the retractor for a lap-shoulder belt, and never route a belt through the handle opening. A lap-only belt must be locked. The lower connector strap tucks under ClickTight the same way, and its storage lid must be closed before the carrier goes on. Up to 4.7" of the base may overhang.

Source: Britax Willow with Aspen base user guide (PDF)

Installing without the base

For baseless use, secure the baby in the carrier before installing it. The manual gives a lap-shoulder belt route with the European belt guide, a standard lap-shoulder route and a lap belt route. Check how your vehicle belt locks; if it cannot lock, you must use a locking clip. When installed, the level line on the carrier label should be level with the ground, and rolled towels or pool noodles in the seat bight can help. The aircraft installation also uses the baseless lap belt route.

Source: Britax Willow with Aspen base user guide (PDF)

Fitting a small baby

The harness ships in the inner loop, for babies up to 11 lb; the outer loop covers 4 to 30 lb. The straps go in the closest position below the shoulders. The hip straps ship in the outer slot for 4 to 30 lb, and an optional inner slot is for babies up to 11 lb; hip straps must not sit under the baby. The infant positioning pillow is only for babies under 11 lb. The carry handle must be in a locked position in the car, and Britax recommends position 1, which is also the carry position.

Source: Britax Willow with Aspen base user guide (PDF)

Cleaning and expiry

Follow the care label for the cover and canopy, and do not bleach or iron. Sponge clean the harness with warm water and mild soap; do not machine wash or machine dry it. Rinse the buckle in warm water without soap or detergent, and test that it clicks with each tongue. Sponge clean the carrier shell, without abrasive cleaners. Stop using the seat and base after 6 years or a moderate or severe crash; the date is on the labels on both.

Source: Britax Willow with Aspen base user guide (PDF)

Is the Willow Infant Car Seat with Aspen Base recalled?

No campaign in the current NHTSA child-restraint data names this model family, and I have not run a separate review for it. Check your seat’s model number and date of manufacture before use.

NHTSA recall search · Recent car seat recalls

Willow Infant Car Seat with Aspen Base: common questions

What are the Willow infant car seat limits?

Rear-facing only, for babies 4 to 30 lb and 17 to 32 in tall, with the top of the head at least 1 in below the top of the shell.

Britax Willow with Aspen base user guide (PDF) (opens in a new tab)

Do I lock the seat belt with the Aspen ClickTight base?

Not with a lap-shoulder belt; the manual says ClickTight replaces the need for a locked or switched belt. A lap-only belt must be locked as your vehicle owner's manual directs.

Britax Willow with Aspen base user guide (PDF) (opens in a new tab)

Can the Willow be used on a plane?

Yes. The manual certifies it for aircraft and gives a baseless installation with the aircraft lap belt. It recommends a window seat and notes it may not fit all aircraft.

Britax Willow with Aspen base user guide (PDF) (opens in a new tab)

How much do the Willow and Aspen base weigh?

Britax lists the Willow car seat at 8.99 lb and the Aspen base at 9.09 lb.

Britax Willow Brook Travel System product page (includes the Willow and Aspen base) (opens in a new tab)

Willow or Arbor?

Britax lists the Arbor for the same 4 to 30 lb range, at 9.9 lb with a 7.4 lb StayTight base, an 18" seat back and a 7.75" shoulder width.

Britax Phases Travel System product page (includes the Arbor and StayTight base) (opens in a new tab)

Answers refer to the model and manual version on this page. Check the instructions supplied with your seat.

Before you buy

Weigh and measure your child. The limits above are the manufacturer’s, and a child has to meet all of them for the mode they will use.
Confirm the exact version. Colors, retail exclusives and model numbers change limits more often than you would expect; Britax lists 3 colors of this seat.
Read the manual before you buy, not after. It is linked above and holds the fit rules, the install methods and the expiry.
Check recalls by model number and date of manufacture, and register the seat with Britax so you hear about the next one.

Sources

Other Britax infant car seats

Model	Top child weight	Seat weight	Width	Usable life
Willow Infant Car Seat with Aspen Base (this seat)	30 lb	8.99 lb	—	6 years
Cypress Infant Car Seat with Alpine Base	30 lb	9.7 lb	16.9 in	6 years
Willow S Infant Car Seat with Alpine Base	30 lb	—	16.9 in	6 years
Willow SC Infant Car Seat with Alpine Base	30 lb	9.3 lb	16.9 in	6 years
Arbor Infant Car Seat with StayTight Base	30 lb	9.9 lb	—	6 years