What happens if my AHC expires while I'm still in the EU?
If you entered the EU on a valid AHC, that same certificate covers up to 6 months of onward travel within the EU and for returning to Great Britain — as long as your dog's rabies vaccination is still valid throughout. If the rabies vaccination expires sooner than 6 months, that becomes your real deadline.
Last verified against gov.uk: 26 July 2026.This page assumes you already know the basic rule
If you haven't already, start with How long is an AHC valid for? for the general 10-day and 6-month rule. This page is for a more specific situation: you're already in the EU, and you're trying to work out your actual deadline to get home.
Rabies vaccination is the real limit
The 6-month AHC window only holds if your dog's rabies vaccination is still valid for the whole period. If the vaccination is due to lapse before the 6 months are up, the vaccination expiry — not the AHC — is your actual deadline. Check the expiry date recorded on your dog's vaccination record before you commit to a long trip.
One AHC covers one outbound trip only
The AHC you used to enter the EU covers that trip. It does not roll over or renew itself for a completely new departure from Great Britain — each new outbound trip from GB needs its own fresh AHC, issued no more than 10 days before you leave.
What to do if you realise your AHC will expire mid-trip
If you're partway through a long European trip and realise your 6-month window (or your dog's rabies validity, whichever comes first) is approaching, plan your return to GB before that date. There's no way to extend or renew an AHC from inside the EU — you'll need to complete your travel and start fresh with a new AHC for your next trip out.
Worked example
You enter France on 1 September 2026 with a valid AHC, and your dog's rabies vaccination doesn't expire until March 2027. Your AHC-based window runs until roughly 1 March 2027 (6 months from entry) — well within the vaccination's validity, so the AHC is your binding limit. If instead the rabies vaccination expired on 1 December 2026, that earlier date becomes your real deadline for getting home.
Common mistake
People sometimes assume the AHC and the rabies vaccination expire on the same schedule. They don't — always check both dates independently and travel home before whichever one comes first.
You may also see the AHC's onward-travel window quoted elsewhere as 4 months. That was the figure before 22 April 2026 — the current, correct figure is 6 months, so if you're reading older content, double-check the date it was written.