Does the microchip need to go in before the rabies vaccine?
Yes. Your dog's microchip must be implanted — and scannable — before or on the same day as the rabies vaccination. If the vaccination happened first, it doesn't count for travel purposes: your dog will need to be re-vaccinated after the microchip is in, and you'll need to wait the full 21 days again.
Last verified against gov.uk: 26 July 2026.Why the sequence matters
A rabies vaccination has to be traceable to one specific, identifiable animal. The vet does this by scanning your dog's microchip and recording that number against the vaccination at the time it's given. If there's no microchip yet, there's nothing for the vet to scan and record — so even a genuine, correctly-administered vaccine can't be linked back to your dog for travel purposes.
What happens if the order is wrong
If your dog was vaccinated against rabies before being microchipped, that vaccination is treated as if it never happened, for travel purposes. You'll need to: (1) Get the microchip implanted (if not already done); (2) Have the vet give a fresh rabies vaccination; (3) Wait the full 21 days from that new vaccination date before travelling. There's no way to backdate or retroactively fix this — the sequence has to be right the first time.
How to check your dog's records
Look at your dog's vaccination record or old EU pet passport for two dates: the microchip implant date and the rabies vaccination date. If you can't find the microchip date, ask your vet to check their records or use the date it was last read and confirmed. If the vaccination date is on or after the microchip date, you're fine.
The 21-day wait, explained
Day 1 is the day after the vaccination, not the day of. So if your dog is vaccinated on 1 August, day 21 falls on 22 August, and your dog is fit to travel from 22 August onward. Don't book travel any earlier than that.
This wait only applies to a first-ever rabies vaccination, or one given after a previous vaccination has lapsed. If your dog is having a routine booster and there's been no gap in their vaccination cover, there's no wait to serve — they're fit to travel as soon as the booster is recorded.
Worked example
Your dog was microchipped in May 2024 and given a rabies booster in June 2026. Because the microchip came first, the sequence is correct. If that booster followed on from a still-valid previous vaccination with no gap in cover, there's no 21-day wait to serve — your dog is fit to travel as soon as the booster's recorded. The 21-day wait only applies to a first-ever rabies vaccination, or one given after a previous vaccination has already lapsed.
Compare that with a dog vaccinated for the very first time in June 2026, microchipped beforehand: the sequence is fine, but the 21-day wait does apply here, counted from the day after the vaccination.
If instead the rabies vaccination had been given in 2020 and the microchip only implanted in 2024, that 2020 vaccination doesn't count for travel purposes at all, and a fresh rabies vaccination (with its own 21-day wait) is needed now.
Common mistake
Owners sometimes assume that because their dog has clearly been vaccinated and clearly has a microchip, the order doesn't matter. It does — this is one of the most common reasons a first-time AHC application gets delayed, because it's discovered only when the vet checks the records at the appointment, not before.