Your animal in, the neighbor’s cat out
A microchip door reads the chip your animal already carries and opens for that number alone, which ends the two problems every flap has: the neighbor’s cat coming in, and your own animal not getting back. The compatibility question is narrow and decisive — most doors read 15-digit FDX-B chips, only some also read the older 9 and 10-digit types, and a chip the door cannot read makes the purchase useless. We compare supported standards, battery life, tunnel depth for thick walls, and the locking modes.
15-digit chips · up to 40 pets · 4 manual modes · weather seals
The cheapest microchip flap here apart from the Cat Mate, reading 15-digit chips for up to 40 animals, with four manual locking modes and double magnetic closing points.
Best for: A first microchip flap on a budget, where the cat’s chip is a modern 15-digit one.
≈ $110
Microchip · 4 × AA · up to 12 months of battery · 4 locking modes
The plain SureFlap: it reads your cat’s chip, keeps the neighbor’s cat out, runs a year on four AA cells, and has no app at all. It is the one most households actually need.
Best for: One or two cats, a wooden door, and no interest in an app — which describes most homes.
≈ $135
Microchip · up to 25 cats · night mode · wood, glass, PVC, metal
A microchip flap with an optional night mode that keeps the cat in after dark, and a fitting kit that covers wood, glass, PVC and metal doors.
Best for: Anyone who wants a curfew without a hub — this is the cheapest way to get one.
Microchip · entry only · 4-way timer · cut-out 7 1/16 × 8 1/16 in
A microchip cat door with programmable timer locking, reading the cat’s existing chip and letting any cat out.
Best for: A single-cat or multi-cat house where the only problem is the neighbor’s cat
Collar key, not microchip · up to 5 keys · dogs to 100 lb · 4 × D cells
A large electronic pet door that opens for a battery-powered collar key rather than a microchip, for dogs up to 100 pounds.
Best for: A large dog, where no microchip door on this shelf is big enough
9, 10 and 15-digit chips · 32 pets · curfew · 4 × C, 12 months
A microchip pet door in white, naming all three chip standards, with a programmable curfew and a three-year warranty.
Best for: A white door frame, if the fourteen dollars and the tag do not matter
9, 10 and 15-digit chips · 32 pets · 6 11/16 × 7 in · 4 × C, 12 months
A microchip pet door for large cats and small dogs, naming all three chip standards, with a collar tag supplied.
Best for: A large cat or a small dog, in a household that wants the chip standards stated
Dual scan · exit permissions per cat · 32 cats · 4 × AA, 12 months
A microchip cat door that scans in both directions, setting exit permission for each of up to 32 cats individually.
Best for: A multi-cat house where one cat must stay in and another must not
Microchip or RFID tag · app · timed curfew · 178 × 170 mm (7.01 × 6.69 in) opening
The large Connect flap: app control, a programmable curfew, and an opening of 178 × 170 mm (7.01 × 6.69 in) for big cats and small dogs.
Best for: A household that wants the cat in before dark without standing at the door — and a cat too big for a standard flap.
≈ $260
Microchip or RFID tag · app monitoring · in-and-out logging
The standard-sized Connect flap: the same chip reading as the plain model, with the app that logs when your cat came and went.
Best for: Anyone who wants to know whether the cat is in or out from work — or to notice, in the log, that it has stopped going out.
Large opening · microchip or RFID · app · timed curfew
The largest flap SureFlap makes with an app: chip reading, curfew, and an opening sized for big cats and small dogs. It is also the largest hole you will cut in a door here.
Best for: A small dog, or a household with both cats and a dog using the same door.
App controlled · collar key supplied · microchip pairing · schedules per pet
An app-controlled pet door with per-pet schedules, remote locking and use notifications, supplied with a collar key.
Best for: A household that wants to see the cat come home from the office
The number of chips it can store decides how many animals are allowed through. That is the structural limit of these devices.
Chip-triggered opening is what sets these flaps apart from a free-swinging hatch. It is their single, sufficient reason to exist.
A cat flap goes into a panel whose thickness runs from three to fifty millimeters depending on the door. The stated thickness range, and whether an extension tunnel exists, decide feasibility.
No, standards vary and some models do not read every type. Check compatibility with your animal's chip before buying.
Depending on the model, the flap locks or unlocks. That behavior is worth knowing — it changes everything while you are away.
By leaving the door open or unlocked at first, then enabling it gradually. The noise of the lock is the main obstacle.
With an adapter and a cut-out made by a glazier. Not an operation to improvise on double glazing.
It keeps the cat indoors at night while still letting it come home. A very common use.
The lock stops it opening and the flap itself can bang. Double-flap models limit drafts.
It varies by model, from a few to several dozen. That is the limit to check in a multi-animal household.
Wood saws cleanly with a template; PVC over a hollow core needs reinforcement round the opening. The door type decides the fitting time more than the flap does.
Check that the model really reads your animal's chip type: not every standard is recognized. Know too what the flap does when the batteries die — locked or unlocked, that changes everything while you are away.
There is no table here, and the reason is in the listings. The figure published most often across these 12 products is key, given by 7 of them — short of the four in five a column needs to compare rather than to display gaps. Each product page says what its own maker published.
Specifications: manufacturer sheets for pet devices and the matching Amazon product pages. Prices and availability: Keepa.
Most recent revision in this category: October 6, 2026.
