Here is the rule that voids more pet-travel paperwork than any other, usually years before the trip is even imagined: a rabies vaccination only counts if the microchip was implanted first. Not on the same visit afterwards. Not the week after. First.
The logic is identity. A rabies certificate is a claim about one specific animal, and the chip is the only identity a border can verify on the spot. A shot given before the chip existed is, as far as the destination is concerned, a shot given to an animal that cannot be proven to be yours. The vaccine worked biologically — it is void administratively, which at a border is the only kind of working that matters.
The quiet failure mode
This one hides well because everything looks right. The certificate is real, the vaccine is current, the dates are all in the past — and the dates are exactly the problem: chip implanted after the dose it is supposed to identify. It surfaces only when someone compares the two dates line by line, which is either your document reviewer months out, or a border officer at the counter.
What to check, and what to do
Pull your pet’s records and compare two dates: chip implant and most recent rabies dose. If the chip came first, you are fine. If it did not, the fix is simple and annoying in equal measure: revaccinate now that the chip is in, and treat that new dose as the real starting line — every downstream step (the 30-day titer wait where required, the destination’s waiting period) counts from it.
Two smaller checks while the folder is open. The chip should be an ISO-standard 15-digit one — some destinations require it, and a non-standard chip may need you to carry your own scanner. And the chip number must appear identically on every document that follows: vaccination certificate, titer report, health certificate. One transposed digit anywhere in that chain is a fresh set of paperwork.