How far ahead should I get travel vaccines?

Last reviewed: 2026-06-14

Quick answer

The earlier the better. The DH recommends arranging a travel health consultation and vaccination at least 8 weeks (roughly 6 to 8 weeks) before departure, because some vaccines take time to become effective and others need several doses spaced weeks apart. For example, the yellow fever certificate only becomes valid 10 days after the dose, and the inactivated Japanese encephalitis vaccine needs two doses 28 days apart. Even if your trip is soon, a consultation is still worthwhile — some vaccines can still offer protection, and a doctor can advise on mosquito-bite and food-and-water precautions.

Lead time matters for travel vaccines, because they don't work the instant you get them.

Why to plan ahead

Time to take effect: vaccines generally need 1 to 2 weeks after the dose to build enough protection.
Multi-dose courses: some vaccines need more than one dose. The inactivated Japanese encephalitis vaccine, for example, needs 2 doses 28 days apart and should be completed at least 1 week before travel; rabies pre-exposure vaccination is also a multi-dose course.
Certificate validity: the yellow fever International Certificate only becomes valid 10 days after the dose.
Appointments and supply: Travel Health Centres require booking, and some vaccines need to be arranged.

Recommended timeline

The DH recommends arranging a travel health consultation at least 8 weeks before departure — the safer approach, especially for trips involving multi-dose vaccines or a yellow fever certificate.

Only remembered close to departure?

Even with just a week or two to go, a consultation is still worth it. Some vaccines can still provide some protection in a short window, and a doctor can give practical advice on mosquito bites, food and water safety, and handling injuries. Late is better than not at all.

Check with the DH Travel Health Centre or your family doctor for what your trip needs.

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