The SureFlap microchip door reads a chip to control opening, keeping other cats out and logging entries and exits. A manual cat door is a simple flap, fixed by magnet or catch in one or both directions, with no individual recognition.

In multi-cat or semi-free-roaming settings, the microchip door earns its place by stopping neighbour cats from entering to eat or fight. A manual door is cheap and easy to fit, and works where the cat is let out at fixed times with no outside cats around.

The trade-off is installation and upkeep: the microchip door needs a cut-out in a panel or wall with matching thickness, plus chip registration and battery changes. The manual door has almost no electronic failure but cannot exclude other animals.

Decide based on whether outside cats are a problem and whether you need entry logs. Before cutting, confirm the door structure and whether the building allows modification. A sudden change in a cat's going-out habit can reflect health or stress.