The Yellow Fever Certificate — Everything You Need to Know

Of all the things that can go wrong at an airport, being turned back at immigration because you're missing a piece of paper about a vaccine is one of the more avoidable ones. And yet it happens. Not rarely — it happens regularly enough that travel clinics will ask specifically about your onward routing before they vaccinate you.

The Yellow Fever certificate — officially the International Certificate of Vaccination or Prophylaxis, informally called the "yellow card" — is the only vaccine documentation that carries legal weight at international borders. Here's what you actually need to know about it.

What it is

It's a small yellow booklet, issued by authorised vaccination centres, that records your Yellow Fever vaccination with a stamp, date, batch number, and the signature of the administering clinician. The format is standardised by the WHO under the International Health Regulations, which means every country that checks it knows exactly what they're looking at.

The certificate becomes valid ten days after vaccination — not immediately. If you're vaccinated on a Monday and fly on Tuesday, your certificate technically isn't valid yet. Most people never encounter this issue, but if you're cutting it very close to departure, it's worth knowing.

How long does it last?

Since 2016, the WHO changed the rules: a single Yellow Fever vaccination is now considered valid for life. Previously certificates needed renewal every ten years. If you have an old certificate that expired under the old rules, it is still valid — the WHO has explicitly confirmed this. You shouldn't need to get revaccinated just because your certificate has an old-style ten-year expiry printed on it.

Some countries haven't caught up with this change in practice, and individual border officials sometimes don't know the rules. If you have an older certificate and you're going somewhere that requires Yellow Fever documentation, it's worth carrying a printed copy of the WHO's updated guidance alongside it.

Which countries actually require it

There are two different situations. Some countries require proof of Yellow Fever vaccination from all arriving travellers, regardless of where they're coming from — this is common across much of sub-Saharan Africa and parts of South America. Other countries only require it if you're arriving from a country where Yellow Fever is endemic — so if you're flying London to Singapore via Nairobi, Singapore may require your certificate because of the Nairobi leg, even though Singapore itself has no Yellow Fever risk.

This second scenario is the one that catches people out. Your routing matters, not just your destination.

What happens if you don't have one

In the best case, nothing — some countries are inconsistent in their enforcement and you'll sail through. In the worst case, you're refused entry and put on the next plane home. In between, some countries will vaccinate you on the spot at the airport and hold you in quarantine for ten days until the certificate becomes valid — which is not how most people want to spend their holiday.

The certificate also has to be the real, stamped physical document. A note on your phone, a GP letter, or a memory of having had the vaccine years ago won't work. The physical yellow booklet, properly stamped, is what's required.

Getting it

Yellow Fever vaccination can only be given at authorised centres — not every GP or pharmacy. In the UK, you can find authorised centres through the NaTHNaC website. In the US, the CDC maintains a list of authorised providers. In the Netherlands, GGD clinics are authorised and generally well-organised for this.

Keep the certificate with your passport. Seriously — treat it like a travel document, because in the countries that check it, that's exactly what it is.

Check Yellow Fever requirements for your destination on WhichVax →