Evenflo Sonus Review

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Evenflo Sonus

Evenflo Sonus

The Evenflo Sonus is the latest budget-friendly convertible car seat in their product line and  checks in at a VERY reasonable price!  We were thrilled to see an additional version of this seat with a 65 pound forward facing weight limit introduced after we wrote this review.  That version of the Sonus remains available while the 50 pound version of the seat seems to have gone the way of the Dodo.

It’s not often that we throw around the term game changer but at this price, it’s hard not to start thinking about the Sonus that way.  Let’s see if the seat matches our expectations.

CSFTL Quick Stats

  • Rear facing weight range: 5-40 pounds
  • Rear facing height range: 19-40 inches and the top of the child’s head is at least 1 inch below the top of the child restraint’s seat back.
  • The top two harness slots can NOT be used rear facing
  • Forward facing weight range: 22-50 pounds (Sonus 65 has a 65 pound upper weight limit)
  • Forward facing age minimum: 2 years old
  • Forward facing height range: 28-50 inches and the tops of the child’s ears are below the top of the child restraint’s seat back
  • Highest harness slot: 18 inches
  • Lowest harness slot: 6 inches
  • 6 harness slots: 6, 8.5, 10.5, 12.5, 15, and 18 inches
  • Expiration: 6 years
  • Lower anchor weight limit: 40 pounds rear facing; 50 pounds forward facing


  • Weight:  10.8 pounds
  • Width at widest point: 18 inches
  • Seat pan depth: 12 inches
  • Crotch buckle: 2 slots, 3.5 and 5 inches from the back of the seat pan
  • Shell height: 25 inches


  • Plush cover
  • Budget friendly MSRP: $79.99.  The Sonus 65 is $99.99.

For a budget friendly car seat, the Sonus has a lot to offer.  The plush cover is very comfortable and won’t overheat most children.  It’s also narrow enough to be a realistic option in some tight spaces.

The Sonus/Sonus Family of Products

There are a few flavors of this seat, here’s a handy chart to show the differences. They all share the same basic shell with 6 harness slots.

Sonus vs. Sonus 65 vs. Stratos

Sonus6 harness slots, 50 pound maximum forward facing weight
Sonus 65Same as the Sonus, only with a 65 pound maximum forward facing weight, and a 2 position recline foot
StratosSame as the Sonus 65, adds an adjustable headrest

Installation: Rear Facing

Evenflo Sonus rear facing

Evenflo Sonus rear facing

When installed rear facing, the Sonus only has one recline angle.  This is perhaps the seat’s biggest limitation since it makes for a pretty significant footprint front to back, roughly 33 inches long.  This meant that in the driver’s seat, I hardly had enough legroom to drive properly.  And I’m not very tall!

Lower Anchors

The Sonus ships with the lower anchor strap in the forward facing belt path. This introduces an extra step in setting up the seat for rear facing use.

To change the lower anchor strap to the rear facing belt path, remove the headrest and peel back the cover to expose the strap, which is in the forward facing belt path.


The Sonus does not include any extra body padding for infants or younger children, though it does include a removable headrest.  The webbing that attaches the headrest to the Sonus is quite short — just long enough to keep it in the proper location but just short enough that our older rear facing models knocked it loose while climbing into the car seat.

The removable headrest can be used at any weight of child, but must be removed for forward facing mode.


The Sonus has two cupholders molded into the seat.  The outside edge of the cupholders is a flat piece, and the inside edge is an elastic strap that all of my models found fascinating.  The outside edge makes for a flat area that may help caregivers safely fit multiple car seats next to each other.

Evenflo does not permit anything to be stored in the cupholders when the Sonus is installed rear facing.

Three Across

The outside of the Sonus’ box claims it’s a good option for three car seats in a row.  We tested this and had mixed results.  In a wider vehicle next to some narrow-ish car seats, it’s possible that the Sonus would be a decent option for three across.  But since it’s 18 inches wide, it’s not the first seat I’d reach for with multiple car seats in the mix.

Rollover Tested

The elephant in the room here is the Sonus’ claim that it’s been rollover crash tested.  This sounds amazing!  One additional measure of security for your Little.  But.

At the moment, there isn’t a federal standard for rollover testing, nor is there one in the works.  There is an FAA inversion standard, which this seat (and all car seats that are approved for use in aircraft) passed.  Evenflo designed and built their own rollover test standard for this seat.  While that innovation is tremendous, without a fully developed standard for this type of test, we just can’t assert much about how the Sonus might perform in a rollover crash.

Fit to Child: Rear Facing

Harness Loops for Tiny Babies

Evenflo Sonus infant harness loops

Evenflo Sonus infant harness loops

The Sonus has a smaller set of harness loops for the tiniest of passengers.  The manual addresses these loops in the ‘Positioning the Harness Strap’ section.  We’d expect this information to be in either the ‘Using the Child Restraint Rear Facing’ or ‘Adjusting the Harness Strap’ sections of the manual.

To use these smaller loops, remove the harness from the splitter plate at the back of the seat’s shell, then attach the smaller loops to the splitter plate.  The crotch buckle can also be routed differently to accommodate the smallest of passengers.

Newborn Doll — without Optional Head Padding

Evenflo Sonus newborn fit

Evenflo Sonus newborn fit

Our newborn Huggable Images doll is 7 pounds and 17 inches long.  She fit quite well in the Sonus.  Since the Sonus doesn’t include infant body padding, it either fits the newborn or won’t work for that child (yet).

The manual contains a caution about consulting the child’s doctor before using the Sonus for preemies. We do note that finding a physician who is also a CPST is quite rare.

Newborn Doll — with Optional Head Padding

Newborn Doll -- with Optional Head Padding

Newborn Doll — with Optional Head Padding

The optional head padding pushed our doll’s head forward a bit so we’d suggest trying the fit both with and without the head padding.

9 Months Old

Evenflo Sonus: 9 months old, 20 pounds, 24 inches

Evenflo Sonus: 9 months old, 20 pounds, 24 inches tall

This tiny charmer is 9 months old, weighs 20 pounds, and is 24 inches tall.  He’s got plenty of room to grow in the Sonus and like our other models, the low sides of the seat made loading him fairly easy.

2 Years, 9 Months Old

Evenflo Sonus: 2 years, 9 months old, 37 pounds, 37 inches tall

Evenflo Sonus: 2 years, 9 months old, 37 pounds, 37 inches tall

This enthusiastic model is not quite so little for his age.  He’s 2 years, 9 months old, weighs 37 pounds and is 37 inches tall.  He’s also on the top harness slot allowed for rear facing in this seat but doesn’t have much growing room left in rear facing mode. We always advocate that children ride rear facing as long as possible.

For a bigger kiddo like this cutie, the Sonus wouldn’t be the longest lasting seat.  We’d suggest the Evenflo SureRide for budget- conscious families who have children on this end of the growth curve.  However, for more average to smaller sized kiddos, the Sonus is a great option!

2 Years, 10 Months Old

Evenflo Sonus: 2 years, 10 months old, 32 pounds, 36 inches tall

Evenflo Sonus: 2 years, 10 months old, 32 pounds, 36 inches tall

This model is 2 years, 10 months old, weighs 32 pounds and is 36 inches tall.  He normally rides in a Chicco NextFit so his dad was used to loading him into a car seat with pretty high sides.  The Sonus’ low sides made it easy for him to climb into the seat on his own — he thought that was great!  His dad reported that harness  straps didn’t adjust quite as easily as they do on  his primary seat.

The upper harness slots are not allowed for rear facing. As this model approaches the seat’s limits it may be inconvenient to have the straps far below his shoulders.

Installation: Forward Facing

My car, a 2016 VW GTI, features a very annoying (yet comfortable for adults who do not ride in car seats) dip in the seat.  This makes fitting many car seats a bit of a challenge since it’s never clear whether to try and set the car seat’s base into that dip or on top of it.  I’m pleased to say that the Sonus fit right into the gap and installed without too much excitement with lower anchors and the vehicle seat belt.  Though not at the same time.

Harness Adjustment

The Sonus’ harness adjusts by removing the harness and threading the webbing through the next slot up.

Fit to Child: Forward Facing

Evenflo Sonus 2 year minimum for forward facing

Evenflo Sonus 2 year minimum for forward facing

The Sonus has an important limit for forward facing use: the child must weigh 22 pounds AND be at least 2 years old.  We applaud this minimum because riding rear facing is safer for those young passengers.

4 Years Old

Evenflo Sonus: 4.5 years old, 48 pounds, 45 inches tall

Evenflo Sonus: 4.5 years old, 48 pounds, 45 inches tall

Like her 2 year old brother above, this kiddo is at the top end of the growth chart.  We were thrilled to have them try this seat for us so we could see how much room they’d have.  At 4 years, 6 months old, she’s 45 inches tall and weighs 48 pounds.  She’s on the top harness slot and though she’s got some room to grow height-wise, she’ll be at the max 50 lb weight limit fairly soon.  We wouldn’t suggest the Sonus for families whose children are on the top end of the growth chart.

Important Information: Where to Find

Evenflo Sonus FAA label

Evenflo Sonus FAA label

FAA Approval
The Sonus is approved for use on airplanes.  The approval sticker is located with all of the other labels on the side of the seat.

Evenflo Sonus date of manufacture label

Evenflo Sonus date of manufacture label

Date of Manufacture
The date of manufacture label is also on the side of the shell of the seat. The Sonus has a 6 year lifespan.  This is mentioned on the label but not in the manual.  We’d love to see it added to the manual as well.

Evenflo Sonus manual

Evenflo Sonus manual

Manual Storage
The seat ships with the manual attached to the shell of the seat.  The manual stores either by attaching it to the plastic lanyard at the top of the seat shell or behind the seat pad.

Pro tip: don’t cut the plastic lanyard when removing the manual from the car seat if you’d like to store the manual using the lanyard later.

Overall Thoughts

The Sonus is a very plush seat for the price.  Because it has an 18 inch top harness slot, it’s likely to last most children for all of their days in a harnessed car seat.  We anticipate that this seat should last the majority of children for all of their harnessed car seat riding days.  At this low price, the Sonus is an excellent, long-lasting option!

CSFTL Celebration Giveaway

To celebrate reaching 400,000 members in our Facebook group, in partnership with our friends at Evenflo Baby we are giving away a Sonus 65 in City Lights to a lucky reader.  Read our terms and conditions, then enter below for your chance to win.

a Rafflecopter giveaway