Cat Door for Sliding Windows
If your window slides open side to side rather than up and down, you can add a cat door without cutting a hole in your wall, door, or the window itself. The insert fits vertically into the track opening created when you slide your window panel open, and adjusts to your window's height.
$90 Bestseller
What counts as a "sliding" window?
Sliding windows — sometimes called slider windows — open by sliding one panel sideways along a track, rather than lifting a sash vertically. This insert is built for that style: it fits into the vertical track opening left when you slide the panel open.
How installation works
This insert is height-adjustable from 16 to 36 inches to match your window's height, with no drilling, adhesive, or permanent hardware. The side edge is padded with a flexible TPU strip for a secure seal and to help prevent shaking. Watch the full process below:
What you get
- Cat passage opening: 7 inches wide by 7¾ inches tall
- Swinging door flap with a 4x4 inch clear acrylic window
- Two-way sliding locks to hold the flap shut in or out; magnet holds it in place when unlocked
- 3D printed in PLA+ plastic with a flexible TPU seal strip
- Patented design
Frequently Asked Questions
Does this work with any sliding window?
It's designed for standard sliding windows where one panel slides along a track, adjusting from 16 to 36 inches tall to match your window's height.
My window is taller than 36 inches — is there anything I can do?
Yes. 8-inch extension panels are sold separately in sets of one, two, or three to extend the height range beyond 36 inches.
Does it work with up-and-down (single- or double-hung) windows instead?
A separate, width-adjustable version is designed for that orientation — see the up-and-down window page for windows that open up and down rather than side to side.
Do I need any tools to install it?
No. It's designed to be tool-free — no drilling, screws, or adhesive. Each door comes with a lock for the sliding panels — be sure to use it to keep the panels from sliding down.