How to choose a pet ID tag: what actually matters

Stainless steel and hard-anodised aluminium keep their lettering far longer than brass or soft plated metal. Plastic tags are quiet and light but crack in cold weather. Whatever you pick, the test is whether a stranger can read it at arm's length after a winter of mud — see why dog tags go blank.

• A hanging tag on a split ring is the standard, and the ring is the weak point. Check it monthly and replace it when the spiral gapes.
• A slide-on tag threads onto the collar strap. Nothing dangles, nothing jingles, and there is no ring to open — but it needs to match your collar's width.
• Attach to a separate ring rather than the D-ring the lead clips to, so lead pressure doesn't work the ID loose.

For dogs in the UK this is not a matter of taste. The Control of Dogs Order 1992 requires the owner's name and address on the collar or on a tag attached to it. A phone number is optional but is the thing that actually gets used.

What you leave off matters as much. Most people now leave the pet's name off, because a stranger calling a dog by name can coax it away, and many leave the full street address off in favour of a postcode and a number. Our guides on what to put on a dog tag and what to put on a cat tag go through the options.

Engraved tags are fixed. Move house, change your number, or need to say the dog is on medication, and you buy another tag — and in the gap, the tag is wrong, which is worse than blank.

This is the real argument for a scannable tag. A QR code pet tag points at a profile you edit from your phone, so the number is always current, and you can add a photo, medical notes and a line about how they behave when frightened — none of which fits on a disc the size of a 10p piece.

• Dogs: strength and readability matter most. A heavier steel tag is fine, and the legal name-and-address requirement applies.
• Cats: weight and snagging matter most. A light, flat tag on a quick-release collar, with no dangling bulk. There is no legal tag requirement for cats, but microchipping is compulsory in England for cats over 20 weeks.
• For cats, also think about the bell question — the research and the risks are in should a cat's collar have a bell.

Two pieces of ID, not one. A microchip as the backstop that works at a vet or a rescue, and a tag as the thing that works in the hands of whoever actually finds your pet in the street. Many owners add a third: an engraved tag carrying the legal details, and a scannable tag carrying everything else.

If you want the reasoning rather than the recommendation, QR pet tag vs microchip vs GPS tracker compares what each one can and cannot do, including where trackers with monthly fees genuinely earn their keep.