It probably depends on the type of neighbourhood you live in, too. Personally, I wouldn't let any cat of mine outside if it wasn't wearing a collar, as it would likey get pinched or taken in by some well meaning person, even if it was chipped. Cats all wear collars where I live, so any that don't are seen as strays. My kitty is indoors, so I don't need to put a collar on her, and was actually advised not to by her breeder due to collars marking the fur, but the harness I take her out on has an identity tag attached to it just in case, god forbid, the lead ever snapped!

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