I have several digs chipped with home again. There is no annual fee and only rarely do I get an email about anything from them. Certainly no spamming. The chip works nationwide, the poster who was told the fee makes it work nationwide is not correct. The fee pays for things like lost pet posters and junk like that. You don't register a chip at your local animal control.
And the other poster is misinformed as well. Even if the reader can't actually READ your chip, it will pick up that the chip is there and the company to contact. So all is not lost.
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