An Animal Health Certificate (AHC) has two separate validity windows, not one. It must be issued within 10 days before your dog enters the EU. Once you're in, the same certificate stays valid for up to 6 months — covering onward travel between EU countries and your return to Great Britain — as long as your dog's rabies vaccination is still in date.
Last verified against gov.uk: 16 July 2026.Your OV (Official Veterinarian) can sign your dog's AHC no earlier than 10 days before you cross into the EU. The signing day counts as day one. So if you're travelling on 15 June, the earliest your vet can sign it is 6 June.
Since 22 April 2026, once your dog has entered the EU, that same AHC keeps working for up to 6 months — for hopping between EU countries, and for coming home to Great Britain. This was extended from 4 months, so if you've read anything saying 4 months, it's out of date. There's one condition worth knowing: if your dog's rabies vaccination is due to expire sooner than the 6 months, that expiry date becomes the real limit, not the AHC's.
Each AHC is good for one outbound trip only. If you're planning another trip from GB later in the year, you'll need a fresh one — even if your last one technically hasn't expired.
Travelling to France on 1 August. Your vet can sign the AHC any day from 23 July onwards. Once you enter France, that certificate is good for onward travel and your return home right through to 1 February — as long as the rabies vaccine is still valid by then.