How to Install A Baby Britax Marathan Car Seat? Complete Step-by-Step Guide

Helen Skeates
Helen Skeates
28 min read

There is a good reason why Britax has been recognized as a leading brand. The One4Life seat and the ClickTight installation are only two examples of the British brand’s many innovations. Choosing a Britax product is as simple as deciding between an infant seat, a convertible seat, or a booster seat as your first step. If you’re unsure about where to begin, this guide will help you figure it out.

5 Advantages of Purchasing a Car Seat

Offers a variety

Choose a car seat that is appropriate for your child’s age, weight, and height when you go to buy one. To do this, read various car-seat reviews to make sure your children are safe and comfortable while driving. This is a fantastic thing because it has three major sorts of vehicle seats. Specifically, there are three types of car seats: infant, convertible, and booster.

Infant Car Seats

These car seats are best suitable for babies during their first year or at least 22 lbs. and are faced in the rear of the car. Since the infant may be easily moved around, it comes with a handle.

Convertible Car Seats

Seats in the back of the car are often bigger and heavier than those in the front. It can accommodate a child weighing 40 to 80 pounds and standing 50 inches tall.

BRITAX Convertible Car Seats: Rear Facing Installation using Lap/Shoulder Belt and One Lock-off - YouTube

Booster Seats

Before anything else, if your child outgrows her car seat, you should already be using a booster seat. If you have a child that is at least four years old and weighs at least 50 pounds, these car seats are for you.

Steps on installing baby Britax Marathan Car Seat

Step 1: If the seat is forward-facing, do not use or install it rear-facing.

At all times, the recline angle must be at least 30 degrees from vertical. A reclining position is the most ideal.

To reduce the danger of severe injuries in an accident, use the LATCH system for installation with lower anchors or top tethers to reduce the time spent on the vehicle’s lap and shoulder belts.

Harness slots must be above the shoulders of older infants who are able to sit up unaided before the harnesses can be removed as they grow older, according to child restraint manufacturer specifications.

Even after side-impact testing, keep the straps taut around the baby/body toddler’s frame.


Rear-facing for as long as possible is the safest option for your child, as long as they meet the weight and height requirements for their particular model of car seat.

The majority of youngsters outgrow a convertible/toddler car seat before they reach the age of four. After a crash, if you’re concerned about the device breaking down, you should consult the user handbook for further information.

How does Britax Frontier convert to booster?

By removing the travel system adaptor, a child’s five-point harness can be simply transformed into a booster seat. To provide a perfect fit for your developing youngster, the headrest and armrests are adjustable.

Britax Frontier has Side Impact Protection (SIP), an energy-absorbing foam liner on both sides of the seat, to provide maximum safety at all times.

For side-impact collisions, this is supposed to decrease whiplash because the child’s body moves forward too much with car lap belts.

Britax Frontiers’ load leg decreases rotational forces induced by weight shifting during sudden deceleration or impact for further protection against ejection in a rollover disaster. A rollover’s rotational force is absorbed by the load leg, reducing the likelihood of it being transferred to your child.

How do you install Britax ClickTight grow with you?

Because of a special function, the Britax ClickTight grows with you and your child.

Britax ClickTight grow with you installation is as easy as the following steps:

Belt paths on car seats should be found close to or behind the vehicle’s headrests (where the top of the back cushion meets the roof). When possible, go through the open end of shoulder/lap belts.

Pull the tether strap until it stops sliding along the strap to ensure the clasp is fully engaged. To secure the chest clip around the child’s chest, firmly press down on the click-tight housing and draw on the harness straps positioned at the front of the seat near the shoulders.

How do you install Britax grow with you ClickTight harness 2 booster car seat?

With its innovative ClickTight safety system, car seats may now be installed with the utmost confidence. Using the lap and shoulder belts in your car provides superior side impact protection for children from baby until booster age.

Installing it takes less than a minute! There will be no more fumbling around with your child’s car seat for the better part of an hour in your new vehicle. All you have to do is click, tighten, and buckle! Rear-facing (for newborns up to 22 pounds) and forward-facing (for children 22 pounds and up to 65 pounds) positions are both simple to change.

You’ll never have to buy another strapped booster car seat again since the five-point harness grows with your child! A excellent option for new parents is Britax’s ClickTight Harness Booster Seat.

Does the Britax car seat turn into a booster?

No, the Britax car seat is not a booster seat. Until your child reaches 65 pounds and is at least 40 inches tall, or seven years old, this product should be used. Before switching to a standard belt-positioning booster, this should be done.

Parents should still put their children in the back seats rather than up front, so they can better observe what’s going on in the road ahead without being distracted by things like video screens or other possible hazards.

How do you use a Britax grow with a booster seat?

The Britax grow can be used in a variety of ways with a booster seat. When your child is still in the car seat, you may then add the backless booster seat on top of it.

Another alternative is to remove the car seat entirely and keep your child in the highback (or backless) section until they are 44 pounds or taller. This provides additional side-impact protection, but at never point should they be allowed to ride unrestrained.

Children should always be strapped in while traveling in a car, even if they’re just two years old! Finally, there are many parents who choose to leave their children in the car seat unattended until they are old enough to ride without a seatbelt in place.

It’s up to you, but it’s critical for your child’s safety that they are correctly strapped into their seats each time you go in the car with them!

Best Britax Infant Car Seats

The ease with which car seats for infants can be used cannot be overstated. Any mother who has taken a sleeping baby out of the car and into a store will attest to its comfortable enchantment. Congratulations to the individual who came up with the idea of allowing us to carry car seats! Of course, one of the drawbacks of infant car seats is that you can’t keep using them indefinitely. Infant carrier seats don’t always work out for us because our babies keep on growing, despite our best efforts to the contrary. Convertible car seats are becoming increasingly popular as an alternative to traditional baby car seats.

I’m not one of those parents, I promise! Because of the many months that I was able to travel with my adorable baby boy in an infant car seat, I’m a big fan of the product. This style of car seat would be my choice if I could do it all over again. Britax likewise recognizes the art of the baby car seat and gives a variety of options for those of us who enjoy them as much as I do!

Britax B-Safe Ultra Infant Car Seat

The Britax B-Safe 35, version 2.0, is the B-Safe Ultra Infant Car Seat.

Are there significant differences between this car seat and the B-Safe 35, which we’ll cover next? Honestly, not at all. Only a few minor characteristics set them apart from one another.

The Britax B-Safe 35 was followed by the B-Safe Ultra, which was an upgrade over the first. The B-Safe 35 came out in 2014, but the Ultra wasn’t available until 2018. Both are still being manufactured today.

Britax’s signature safety features, such as impact-stabilizing steel frames and energy-absorbing bases, are present in both B-Safe models. Both car seats feature a 35-pound weight restriction and are compatible with travel systems.

However, there is a distinct distinction between the two. The Ultra, on the other hand, has six harness adjustment positions, while the B-Safe 35 has only four. With the Ultra, you don’t have to rethread your seat belt because the harness can be modified by moving the seat’s headrest forward or downward. Harnesses don’t have to be threaded through many slots in the shoulder straps!

Most of the following distinctions are for the benefit of the user, but they’re well worth it. The Ultra car seat has a belly pad that can be flipped forward. Basically, the buckle is protected by a cover that prevents it from reversing while it is not in use. As a result, there will be no more digging for the buckle under your child’s butt!

A European belt guide is also included with the Ultra. Because it may be temporarily installed in a vehicle without the base, the car seat is now suitable for carsharing. Increasing numbers of corporations are including ride-sharing into their chairs as the popularity of the service grows.

Britax B-Safe 35 Infant Car Seat

The Britax B-Safe 35 Infant Car Seat is a popular choice among customers.

The B-Safe 35 is standard equipment in several of Britax’s most popular car seats. As expected, this award-winning car seat is unrivaled in both safety and comfort.

As a first priority, your infant is safe from harm on the way home from the hospital until they weigh 35 pounds or more. As a precaution, your infant is protected at the head, neck and torso by side impact protection in the case of an automobile collision.

The SafeCell material used in the construction of the seat aids with energy absorption in the event of an impact. An impact-stabilizing steel structure also forms the seat’s foundation. Your child’s safety is the primary goal of all of these features.

Even if your infant is secure, are they comfortable? Absolutely. The cover on this Britax car seat is removable and machine washable, making cleanup a breeze. A detachable head pillow is included for the tiniest of babies. There is also an extra-large canopy to keep out the rain!

In order to use the B-Safe 35 seat, you must have a Britax stroller that is compatible with this seat.

Best Britax Convertible Car Seats

Nowadays, a product is considered vintage if it doesn’t have at least two unique applications. This is when a convertible car seat comes in handy!

If you don’t want to use an infant car seat, this is the sort of car seat for you. Car seats that can be used in both the rear and forward facing positions are a one-and-done investment. A convertible car seat is an excellent baby shower gift because it eliminates the need to purchase a car seat in the future.

In light of this, is a Britax convertible car seat deserving of a place on your baby shower wish list? Definitely. It’s hard to go wrong with Britax car seats when it comes to safety, style, and longevity. In addition, I’d want to say hi! One car seat for the rest of my life!

ClickTight Convertibles: Rear-Facing LATCH Installation - YouTube

Britax One4Life ClickTight All-In-One Car Seat

There’s just one car seat you’ll ever need: the Britax One4Life ClickTight All-In-One Car Seat!

Typically, you’ll need to acquire at least two car seats; in some situations, even three! It’s possible to start off with an infant car seat and then move on to a convertible car seat. You’ll need a booster at some point.

That’s how it’s always been done. Britax has taken this idea and turned it completely around. For your child, this is the only car seat you’ll ever need. Ever. It goes from infancy to a whopping 120 pounds in weight! It boosts as it rear-faces and forward-faces!

If you’re just going to buy one car seat, you probably want to make sure it’s the safest one. There’s nothing to worry about. It has a SafeCell crumple zone to absorb energy, a V-shaped tether to reduce movement, and a high-strength steel frame to keep it all together.

You’ll be blown away by how simple it is to use this seat. Using your car’s seat belt, you can easily install this seat. No rethreading of the harness or the headrest is required. What’s the portion that I enjoy most? Dishwasher safe cupholders may be removed and cleaned. Is there anything better?

While normal car seats run hot, the One4Life aims to keep your child nice and cool, thanks to ventilated mesh fabric and built-in cooling channels for maximum airflow.

Britax Boulevard ClickTight Convertible Car Seat

Normal car seats can get hot, but the One4Life’s ventilated mesh fabric and built-in cooling channels for optimal ventilation are designed to keep your youngster cool.

Yes, the convertible car seat can be used in either the rear-facing or forward-facing position. Up to 40 pounds of weight can be accommodated in the rear-facing position with this car seat. If you’re a first-time parent, you may be unsure whether or not gaining 40 pounds is important. “It’s as good as it sounds.” To put things into perspective, my 3-year-old son weighs less than 40 pounds!

Britax’s exclusive safety features ensure that this car seat is safe for your child. With a steel frame, you can’t argue! Additionally, Britax’s five-point safety harness is another feature that keeps your kid safe.

The premium fabric and padding used in the Boulevard’s car seat make for a comfortable ride. When the inevitable happens and your child’s car seat is ruined by a spill, this soft cover is simple to remove (or two).

Is it really that simple to keep it clean? Customer JayC proclaimed this seat the “greatest car seat EVER” and was eager to bring out the ease of cleaning as a major selling factor. That they “don’t need a YouTube video just to put the cover back on” is a big plus for them. JayC, I agree.

And this is my favorite color scheme for a Britax car seat. This geometric mosaic is called Vector, and it’s made out of brilliant colors. A charming retro style brightens up the entire car seat, in my opinion.

In our comparison post, we’ve compared the Boulevard with various Britax car seats.

Britax Emblem 3 Stage Convertible Car Seat

In terms of quality, the Britax Emblem 3 Stage Convertible Car Seat is one of the best seats on the market at a reasonable price.

The Britax Emblem is a symbol of the company’s values, which may be a little too obvious to mention. It’s secure, simple to use, and downright chic. Plus, it’s a budget-friendly choice.

2018 saw the arrival of Britax’s Emblem, a budget-friendly option. If you’re on a budget, this convertible car seat from Britax is an excellent option. In this car seat, however, there are no compromises and no corners have been cut.

In fact, a client has proclaimed the Emblem the “Rolls Royce of car seats,” despite its price. That kind of review is hard to refute! Installing the seat is a snap, and the seat has an impressive list of safety features and a pleasant user interface to back up this assertion.

There aren’t any fun patterns available for the Emblem car seat. Even though the cover is removable and so simple to clean, you won’t mind much.

The lack of cupholders on the seat may leave you unsatisfied. In the end, where do you keep the sippy cup and the Goldfish crackers, anyway? The good news is that Britax has a cupholder accessory that is compatible with this seat. In addition, it’s dishwasher-safe!

Britax Allegiance 3 Stage Convertible Car Seat

Convertible car seats like the Britax Allegiance 3 Stage Convertible Car Seat are known for their dependability and durability.

Is this Britax car seat convertible worth your loyalty? A resounding yes, in my opinion. The purple polka-dot pattern reminds me of Minnie Mouse, but that’s not the only reason I say this.

A lot of people are excited about the Allegiance car seat, which has been in production since 2018. Parents love the cushioned crotch buckle cover because it prevents their children’s legs from getting pinched. It also doesn’t fall off or get lost. While I can sympathize with your plight, the buckle cover of a non-Britax car seat was never seen again after the first month.

Even when you remove the car seat’s buckle, you’ll find it to be an ideal place to rest your head. Even the tiniest babies are kept warm and cozy thanks to the removable body pillow. Even older babies and toddlers will be able to take a sleep thanks to the soft padding and breathable textiles of the seat cover.

There’s a fine line between comfort and safety. To be expected from a Britax product, this car seat is equipped with a long list of high-quality safety features as standard.

Best Britax Booster Car Seats

The booster seat is the final step in the progression of car seats! Booster seats are the only thing standing between you and a world without car seats.

However, even though it is the final stage, it is worth doing correctly. As parents, we all know the importance of car seats for children under the age of two. There is less emphasis on car seat safety as children get older. As a result of this, some parents may assume it’s fine to be lenient with the usage of booster seats.

Most youngsters cannot be kept secure in a car alone by using a seat belt. When they utilize seat belts designed for adults, their small height puts them at risk. National Highway Traffic Safety Administration recommends that children between the ages of 8 and 12 use a booster seat until they are at least 4’9″ tall.

Britax, on the other hand, features high-tech booster seats that are safe, long-lasting, and stylish.

Britax Highpoint 2-Stage Belt-Positioning Booster

New to the Britax lineup is the Britax Highpoint 2-Stage Belt-Positioning Booster.

Despite the absence of a harness, this booster seat can be used as a high back booster or a low back booster.

The Highpoint’s unique design sets it apart from the rest of the booster seats on the market. In order to ensure appropriate seat belt use, the Highpoint seat features a SecureGuard clasp and color coded guide belts.

In addition, the Highpoint’s roomy interior will make for a comfortable ride for your child. Despite its size, it doesn’t compromise on safety. Additionally, the head restraint may be quickly adjusted from a 10-position position. With the two armrests, they’ll be able to relax comfortably.

Children weighing 40 to 120 pounds can utilize the high back version. The backless booster can be used by children weighing 48 to 120 pounds. Make sure to adhere to safety guidelines and do not switch to the backless version until your child is 48 pounds and over 46 inches tall.

Britax Grow with You ClickTight Harness-2-Booster Car Seat

When you grow, so does the Britax Britax has done it again with the ClickTight Harness-2-Booster Car Seat.

When it comes to 2-for-1 bargains, Britax’s engineers seem to have a penchant for it. This seat looks like a booster, but it’s actually a car seat with a harness. In order for children to use the car’s seat belt effectively, traditional booster seats are employed. That’s what this seat does, but before that, it functions like a low-profile car seat!

The typical car seat method can be bypassed with the use of this unique combo seat. With the Britax Grow with You Booster Car Seat, youngsters as small as 25 pounds can be safely secured in a car seat. Essentially, you may save money by switching directly from an infant seat to this booster set.

In addition to the SafeCell technology, steel frame, and two levels of side impact protection, the Grow with You contains all of Britax’s standard safety features. In addition, the ClickTight mechanism makes installation a breeze. Close, open, and thread!

Ventilated mesh covers the seat to keep you cool and comfortable while driving. The two cupholders that can be filled with Goldfish crackers will be especially appreciated by your child.

Children weighing 25 to 65 pounds can use the harness front-facing component. From 40 to 120 pounds, the booster seat can support you. Always double-check with your local authorities to see when youngsters can switch from one type to another.

Britax Skyline 2-Stage Belt-Positioning Booster Car Seat

Britax’s line of booster seats has been expanded to include the Skyline 2-Stage Belt-Positioning Booster Car Seat.

This seat, like the Highpoint, can go from a high-back booster to a backless booster. Mama, you’re going to love having so much extra legroom in the back seat once you can use that backless booster seat!

You can’t go wrong with either the Highpoint or the Skyline because both are booster seats. You should think about how many cars you have and how big your family is while making this decision.

Britax - Marathon ClickTight Convertible Car Seat, Verve in 2022 | Car seats, Convertible car seat, Britax marathon clicktight

Previously, we talked about the Highpoint’s spacious design. The Skyline, on the other hand, has a more streamlined appearance and can accommodate three passengers across! A third of these booster seats, or perhaps one of these plus two other seats, will fit perfectly here. We’re looking for large families to join us!

The Skyline is equipped with all of the safety measures that you would expect to find. Side impact protection is provided by two levels of foam-lined shell cushioning. EPP-foam is also used on the seat’s sides and back for energy absorption.

The Skyline is good for 10 years from the date of manufacturing, so it’s a long-term investment for you and your family.

Britax Midpoint Belt-Positioning Booster Seat

Another current Britax booster option is the Midpoint Belt-Positioning Booster Seat.

The Midpoint might be the greatest option for you and your family when it’s time for a “big kid” seat. While your child may feel like an adult in this seat, they will be just as safe as they would be in any other type of baby car seat. ”

Your child’s head, neck, torso, and pelvis are all protected by the deep walls of this comfortable seat. A two-layer energy-absorbing foam shell surrounds them on all four sides.

Britax’s Midpoint has a particular fondness for the number two. It contains two cupholders and two armrests in addition to the two layers of side impact protection. Dual Comfort breathable and moisture-wicking materials are also used to create the seat.

There’s good news for parents of tall children: Head restraint adjustment is a cinch with this booster’s 10-position quick-adjust feature. This seat isn’t going to be able to keep up with your child’s rapid weight gain.

If necessary, the Midpoint may be stacked three high in the trunk of most cars. However, you’ll have to take off the booster’s two cupholders in order to do this. Indeed, the cost of having three children fit in one automobile is a small price to pay!

Your child will be safe in this high back booster seat until they weigh 120 pounds. One year of warranty and a 10-year expiration date.

How Britax Car Seats Compare

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Which Britax car seats are part of travel systems?

Almost any Britax travel system includes an infant car seat. Car seat adapters are included for the strollers in these systems.

As a result, the convertible car seat and the booster seat are not compatible with the travel system. These seats are designed to remain firmly in place within your car. If you want a complete set of car seats for your child, consider Britax’s line of newborn car seats.

When do Britax car seats expire?

There are a variety of expiration dates for car seats. There is a common rule of thumb with Britax car seats. Six years from the date of manufacture, infant car seats must be replaced. For seven years, convertible car seats without the ClickTight installation technology lasted. ClickTight car seats have a 10-year shelf life!

In order to determine when your Britax car seat is out of date, you’ll need to look at its manufacturing year. Each car seat has a label with this date on it, and you may find it by consulting the seat’s instructions. Such a label can be found on both the seat and the base of Britax B-Safe infant car seats.

How do you install Britax car seats?

Installation is dependent on the seat you select. – The LATCH system is used by some Britax car seats, while the ClickTight technique is used by others.

Most car seats can be installed using the LATCH system. Seat belts and lower anchors may be involved. Anchors built into the seat cushions are now standard on many new cars. These can be used in conjunction with the seat’s top anchor to secure the car seat.

Using ClickTight couldn’t be easier. In order to clip the seatbelt in, a panel in the automobile seat must be raised. Locking the seatbelt in place is the final step in securing the vehicle.

Without visual aids, installation can be difficult. Fortunately, Britax provides installation videos to make the process easier for you to understand.

How do you remove Britax car seats from the base?

Only infant car seats can be removed from the base of Britax car seats. Convertible car seats are a one-stop shop for families on the go.

An infant car seat can be easily removed from the base of a Britax. You’ll find a release lever on the back of the carrier. Pulling and holding the lever will let you get the carrier out of the base.

This release lever is still present on new Britax infant car seats, and it serves the same purpose. Consult your product’s handbook if you have an older model.

Where can I find Britax car seat manuals?

All of Britax’s product manuals can be found on the company’s official website. The list is extensive and contains instructional films, as well as manuals for Britax items that have been discontinued.

When you buy a car seat, you’ll get a printed copy of the instruction handbook. But, don’t we all prefer an electronic version? You’re right, I get it.

Are Britax car seats approved for airplane use?

The majority of Britax car seats are approved by the Federal Aviation Administration (FAA). To be on the safe side, double-check your car seat. “This restraint is certified for motor vehicle and aviation usage” will appear in red on your seat’s label if it is approved for airline use. In addition, the organization suggests contacting your airline to confirm your upcoming flight details.

Because these boosters require both a lap and a shoulder belt, they are not permitted for use on airplanes. Please be aware of this. Seats like Skyline, Highpoint, and Midpoint are included. It is possible to utilize the Grow With You booster seat with a harness.

Wrap Up

All of Britax’s car seats, from infant carriers to convertibles to boosters, are excellent. These chairs stand out from the crowd thanks to brand-specific features like SafeCell Technology and cutting-edge developments like the One4Life.

Britax car seats are the best on the market. Regardless of which model you choose, you’re getting a high-quality car seat that you can count on for many years to come.

If you’re looking for the best Britax stroller, be sure to check out our buying guide. The best travel systems from the company will be revealed soon.

Helen Skeates

Helen Skeates

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