Does an indoor cat even need a tag?
Yes, because even a cat that stays in can slip out through a cracked window, a stairwell door, or in the panic of moving house. A cat with no marking outside looks like a stray, so hardly anyone starts looking for an owner. A visible tag says at once that someone is waiting for it.
A lost cat usually hides close to home and stays silent for a long time. When someone finally spots it, the tag decides whether they think “someone's cat, I should return it” or walk on by. It's what sets everything else in motion.
A microchip matters, but it's invisible and needs a scanner at a vet or shelter. A tag can be scanned on the spot by the first person with a phone, so one doesn't replace the other.
What makes a collar safe for a cat?
A safe cat collar has a breakaway buckle, a clasp that releases under pressure. If the cat snags the collar on a branch, a fence or a handle, it slips free and doesn't get trapped. It should be light, well-fitted and unobtrusive, not stiff and heavy.
Check the fit with the simple two-finger rule: two fingers should slide easily between collar and neck. Pick the lightest tag you can, since cats hate weight, and get the cat used to it gradually, ideally around play and food.
Since a breakaway collar can, by design, come off, treat it as a pair with a microchip. The collar gives quick contact on the outside, while the chip stays as a permanent backup should the tag ever go missing.
How does a QR tag help a cat get home?
The finder holds a phone to the code and within seconds sees the cat's profile: a photo, the name, a note that it's lost, and a button to call you. They install nothing and set up no account, and there's no battery in the tag to run flat.
The profile is editable, so you change the number or switch on a “lost” status without swapping the tag. If you want to untangle the difference between cat documents, see our piece on cat ID versus a pet passport, and while you're at it, what's worth putting on the tag itself.