Companion Backseat Extender™ for Dogs
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Create a more complete, comfortable backseat travel space with the Animals Matter® Companion Backseat Extender™ for Dogs, part of the Backseat Extender Safety System. Designed to help fill the open footwell area behind your vehicle’s front seats, the extender adds structured, cushioned support where there would otherwise be an open drop-off space between the front and rear seats.
Use one Companion Backseat Extender™ behind a single front seat, or use two extenders with the Companion Backseat Bridge to help fill both rear footwells and the center gap for a more continuous, comfortable backseat surface.
Build the Backseat Extender Safety System
The Backseat Extender Safety System is a modular three-step travel support system designed to help create a wider, more stable-feeling backseat platform for your companion.

Step 1: Start with Two Backseat Extenders
Place two Animals Matter® Companion Backseat Extenders™ in the rear footwells behind the front seats to help fill both open footwell spaces and create a wider cushioned backseat platform.

Step 2: Add the Animals Matter Backseat Bridge
Place the Companion Backseat Bridge between the two installed extenders to help fill the center gap and create a more continuous backseat surface.

Step 3: Complete the System
With both rear footwells and the center gap supported, the system helps create a more complete, cushioned, and stable-feeling backseat travel area for your dog.
Why This Travel System Is Different
The Companion Backseat Extender™ is more than a loose cushion or basic car filler. It is part of a modular backseat support system designed to help reduce open footwell gaps where dogs may step, slide, or fall during travel.
Crafted with a supportive CertiPUR-US® certified foam component, each extender provides structure without the weight of hard plastic or wood. The premium upholstery-grade fabric cover feels soft, tailored, and refined inside the vehicle, while the removable zippered design makes care simple between everyday errands, weekend drives, and longer road trips.
Key Features
- Luxury backseat extender for dogs
- Helps fill the open rear footwell area behind the front seat
- Use one extender for one footwell or two extenders for both rear footwells
- Companion Backseat Bridge helps fill the center gap between two extenders
- Part of the modular Backseat Extender Safety System
- Crafted with a supportive CertiPUR-US® certified foam component
- Premium upholstery-grade fabric cover for a refined vehicle interior look
- Removable zippered cover for cold-water machine washing and line drying
- Available in Small and Large
- Available colors: Charcoal, Stone, and Black
Best For: Companion parents who want to create a more comfortable, supportive, and level backseat travel area for their dog. For the most complete setup, use two Companion Backseat Extenders™ with the Companion Backseat Bridge.
Travel Safety Reminder: Always use an appropriate dog restraint or vehicle safety harness while driving. The Backseat Extender Safety System helps create a more supportive backseat surface, but it is not a restraint system on its own.
*It is important to always restrain your dog while traveling to ensure their Safety.
Easy Returns and Exchanges: Our return policy and Options for returns and exchanges.
Size Chart
Dimensions:
Large System: Includes 2 Large Extenders + 1 Center Bridge Connector. Each Large Extender measures 24"L x 13"H x 11.5"D.
Small System: Includes 2 Small Extenders + 1 Center Bridge Connector. Each Small Extender measures 19"L x 13"H x 11.5"D.
Single Large Extender Only: Includes 1 Large Extender only.
Measures 24"L x 13"H x 11.5"D.
Single Small Extender Only: Includes 1 Small Extender only. Measures 19"L x 13"H x 11.5"D.
Center Bridge Connector Only: Includes 1 Center Bridge Connector only. Measures 9"L x 13"H x 9.5"D. This piece is not intended to be used by itself and requires 2 extenders.
Care
Cover unzips for cold water, machine wash, and line dry—no Heat, Bleach, or Bleach Alternatives.
Inserts and Foam are not washable. Please spray a solution of half white vinegar and half water on the soiled area and air dry.
What does the Companion Backseat Extender™ do?
The Companion Backseat Extender™ helps fill the open rear footwell space behind a front seat, creating a more continuous, supportive backseat surface for your dog during travel.
Why is it important to fill the rear footwell?
Open rear footwells can create a drop-off area where dogs may step, slide, or fall during travel. Filling that space helps create a more supportive and comfortable backseat setup.
Can the Backseat Extender Safety System help keep my dog from falling into the footwell?
Yes. The system is designed to help fill the open footwell area where dogs may step, slide, or fall. It should always be used with an appropriate dog restraint or vehicle safety harness while driving.
How many Companion Backseat Extenders™ do I need?
Use one Companion Backseat Extender™ to fill one rear footwell. Use two extenders if you want to help fill both rear footwells and create a wider backseat platform.
What is the Companion Backseat Bridge?
The Companion Backseat Bridge is the center piece that sits between two installed Companion Backseat Extenders™ to help fill the small gap in the middle.
How does the full Backseat Extender Safety System work?
For the most complete setup, use two Companion Backseat Extenders™ with the Companion Backseat Bridge. Together, they help fill both rear footwells and the center gap for a more continuous backseat surface.
Is the Companion Backseat Extender™ a restraint system?
No. The Companion Backseat Extender™ helps create a more supportive backseat surface, but it is not a restraint system by itself. Always secure your dog with an appropriate vehicle restraint or safety harness while driving.
What is the safest way to use the Backseat Extender Safety System?
Use the correct size extender for your vehicle, complete the setup with two extenders and the Companion Backseat Bridge when filling both footwells, and always pair the system with an appropriate dog restraint or vehicle safety harness.
What sizes are available?
The Companion Backseat Extender™ is available in Small and Large sizes. Measure your rear footwell area and review the size details before choosing.
Is the cover washable?
Yes. The removable cover unzips for cold-water machine washing and line drying. The foam insert is not washable.
Is a car seat extender the same thing as a backseat extender?
Yes. "Car seat extender," "dog car seat extender" and "backseat extender" all describe the same thing: a cushioned block that fills the open footwell space behind a front seat so the rear of the vehicle becomes one continuous surface. Ours is the Companion Backseat Extender™. It is not a car seat and it is not a restraint, and it should always be used alongside an appropriate vehicle restraint or safety harness.