How we chose these smart cat flaps
A cat flap is one of the few smart home devices your pet interacts with without your consent, so we ranked reliability and safety first: microchip recognition that works for the whole household, a lock you can trust at night, and batteries or power that will not leave a cat outside. Next we looked at what the smart part actually delivers — curfews, presence tracking, notifications — and whether it can be pulled into Home Assistant notifications and automations. We checked each product against the maker's own pages and the Home Assistant documentation, and we excluded anything with no confirmed UK stockist or no verifiable specification. Prices move often, so treat the bands in the table as a guide and check the current retailer price before buying.
One honest limit: we have compared published specifications and independent reviews here, not run a six-month lab test on every flap, so the notes below are about fit and trade-offs rather than star ratings.
The best smart cat flaps for UK homes in 2026
1. SureFlap Microchip Cat Flap Connect — best overall
Who it's for: Households that want a proven microchip flap with app control and a real, supported Home Assistant integration.
The SureFlap Connect registers up to 32 pets by their existing microchip (or an RFID collar tag), runs on four AA batteries for roughly six months, and offers four modes: open, entry only, exit only and locked. DualScan lets you choose which cats may go out and which must stay in. The app adds curfews, activity history and low-battery alerts once the separate Sure Petcare Hub is plugged into your router.
The catch is cost and range. Retailers have listed the flap alone at roughly £115–£175 with the Hub costing around £50, and Expert Reviews noted the mandatory hub as the main drawback, plus extra cost for glass or wall installation. The Hub also talks to the flap over a short-range wireless link (one UK retailer guide puts it at roughly 10m through a couple of internal walls), so a flap far from the router can drop out.
For Home Assistant, the core Sure Petcare integration exposes each pet's inside/outside presence, flap battery level, connectivity and three lock entities (locked in, locked out, locked all), plus actions to set the lock state and override a pet's location. It uses cloud polling and needs the Hub, so expect a short delay and no offline control. If you already run a feeder from the same brand, see our best smart pet feeder UK guide, which uses the same integration.
2. OnlyCat — best for stopping prey coming indoors
Who it's for: Owners of hunting cats who are tired of finding mice and birds on the carpet.
OnlyCat combines microchip recognition with a night-vision camera and an on-device neural network that spots prey in the cat's mouth and keeps the door shut until the cat drops it. It also gives per-cat curfews, video notifications and an activity feed. It is designed for cats up to about 6kg, needs mains power over USB-C rather than batteries, and requires Wi-Fi for set-up; the one-time-purchase version can keep running door functions offline afterwards, while the subscription version needs an active connection.
The catch is price and supply. OnlyCat lists prices in euros starting around €327, well above the SureFlap, and a UK installer has noted that production is still ramping up so orders are first-come, first-served. The camera also points at your own doorstep, so think about a shared path or neighbour's view.
For Home Assistant there is no official integration, but a community one is installed through HACS from the OnlyCatAI/onlycat-home-assistant repository. It adds a device tracker for pet location, sensors for flap connection, lock state and contraband (prey) events, unlock and reboot buttons, and services to set a pet's location or change the door policy. You create an API key in the OnlyCat app's developer mode, so it is cloud-dependent, and editing pet profiles is not yet supported. See how custom components work before installing.
3. Cat Mate Elite Microchip Cat Flap — best curfew without an app
Who it's for: Anyone who wants a night-time curfew and cat-location display but does not want another cloud account or a hub.
The Cat Mate Elite stores up to nine cats by microchip or ID disc, includes a timer for night-time curfews, and shows lock status, each cat's inside/outside state and time since last use on an integrated LCD. It uses four AA batteries and one retailer lists roughly 12 months of life and a three-year guarantee. It suits single or multi-glazed panels, UPVC, wooden doors and walls.
The catch: nothing here is connected. There are no notifications, no history in an app and no Home Assistant integration, so you cannot tell from the sofa that the cat is stuck outside. Retailers have listed it from around £150, so it is not a budget flap either. It earns its place as the least fiddly reliable option.
4. PetSafe Microchip Cat Door — best simple multi-pet flap
Who it's for: Big multi-cat households that just need selective entry and a manual four-way lock.
PetSafe's microchip flap can be programmed for up to 40 pets with a one-button set-up, and its four-way lock gives you locked, unlocked, enter-only and exit-only. It is battery powered and has no app or Wi-Fi, which is a feature if you would rather avoid another device on your network. Price varies by retailer, so compare before buying.
The catch is the same as the Cat Mate: no curfew timer, no notifications and no Home Assistant path, so you would be switching modes by hand.
See the PetSafe Microchip Cat Door
Does a smart cat flap work with Home Assistant?
Yes, but only two flaps here have a route in. The SureFlap Connect uses Home Assistant's built-in Sure Petcare integration, and OnlyCat uses a community HACS integration. Both rely on the vendor's cloud, so they are convenient for presence automations, not for anything safety-critical.
A practical pattern is to use the pet's presence entity as a trigger or condition. For example, you could pause a motion-triggered light or a pet camera alert when the cat is confirmed outside, or send a phone notification when the flap has locked the cat out overnight. Remember to have a physical fallback: never rely on an integration, an app or your Wi-Fi to let a cat back in.
What should you check before fitting a smart cat flap?
Measure the door first. The SureFlap Connect has a 14.2cm wide by 12cm high opening and needs a cut-out of about 16.5cm by 17.1cm in a standard door, and glass or wall installs need adapters or a professional. A larger cat may not fit any of them, so check the opening against your cat's shoulder width, and note that OnlyCat is specified for cats up to about 6kg.
Next, decide where the cat's microchip will be read. All the microchip flaps here read the chip your vet already implanted, so you do not need a collar tag, though SureFlap sells RFID collar tags if a chip is unreliable. Finally, put batteries on a calendar: four AA cells last roughly six to twelve months depending on the model, and it is worth reading the manual to see what your flap does when the batteries run flat.
Who should skip a smart cat flap?
Skip the Flappie if you are in the UK: it offers biometric cat recognition and local AI prey detection, but its maker lists delivery only to Switzerland, Germany and EU countries, quotes CHF 449, and says it cannot currently be integrated with smart home systems. Also skip any smart flap if your cat uses a window or other exit, because activity logs and presence tracking will be inaccurate, as Expert Reviews noted. In that case a simple non-connected microchip flap is cheaper and just as useful.
Finally, if your only problem is a neighbour's cat wandering in, a plain microchip flap solves it and you can skip the Hub.
