Pet Travel Guides
Does Dog Size Matter When Travelling Between Britain and Ireland?
By Lorna Mullins, Founder of Fetch Travels
Published 20 September 2026
Last fact-checked 20 September 2026
Owners of larger dogs often ask me whether the paperwork changes because of their dog's size. The short answer is generally no, the core microchip, rabies, travel-document and tapeworm requirements don't become different simply because a dog is small, medium or large. The practical answer is very different: size can affect almost every transport decision built around that paperwork, which is really where my job starts.
Where size doesn't usually change the rules
A Chihuahua and a Great Dane travelling from Great Britain to Ireland are subject to the same core health-document requirements. The tapeworm-treatment window is the same. An Animal Health Certificate can cover up to five pets, subject to non-commercial movement limits.
Where size makes a real difference
- Kennels: get the internal dimensions for the exact vessel; the dog must stand, turn and lie down comfortably.
- Pet cabins: operators may limit pet number, combined weight or size, and availability can sell out early.
- Foot travel: a large dog, luggage and several train changes can be demanding for one person.
- Stations: dogs cannot use seats, and a large dog must not obstruct aisles.
- Taxis: book a pet-friendly vehicle and disclose approximate size.
- Air travel: acceptance, crate specifications and cargo arrangements are highly size-dependent.
Size and breed type are not the same issue
A large dog is not automatically a banned or restricted type, and a smaller dog is not automatically outside breed-specific rules. Great Britain restricts specified dog types, including the XL Bully, and Ireland prohibits the import, breeding, sale and transfer of XL Bully dogs, with exemption arrangements for dogs already legally kept there. Check the current rules before travel.
Questions to ask the ferry company
- What are the kennel's internal dimensions?
- Are stairs or a high threshold involved?
- Can the owner remain with the dog in a lounge or cabin?
- Is there a maximum weight or number of pets?
- Where is the exercise area?
- Does the dog need a muzzle?
- What happens if the vessel changes?
Keep reading
Related pet travel guides
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Sources
Check the current guidance
- GOV.UK, Ban on XL Bully dogs
- GOV.UK, Bringing more than five pets to Great Britain
- Irish Ferries, Pet Travel FAQ
- National Rail, Train travel with pets
This guide is provided for general information and reflects rules and prices we understood to be accurate on the “last fact-checked” date shown above. Pet-travel rules, ferry and transport-provider policies, and veterinary costs can all change, and some, including Irish public transport’s pet policy, are under active review as we publish this. Always confirm current requirements with the official sources linked in this article, and with your vet, before booking or travelling. Fetch Travels provides in-home pet sitting in London; we do not currently offer pet-travel planning, veterinary coordination, or relocation services.