As of early 2026, the Yellow Fever vaccine requirement for Kenya depends on where you are traveling from. A Yellow Fever Vaccination Certificate is strictly mandatory for all travelers (aged 1 and older) arriving from countries with a risk of yellow fever transmission, including layovers of more than 12 hours in those countries. If you are flying directly from the UK, USA, or most of Europe, it is generally not required for entry, but it is strongly recommended for your personal health, especially if you plan to go on safari in high-risk areas like the Rift Valley or western provinces. Note that some areas like Nairobi and Mombasa are considered low-risk. However, because the vaccine provides lifelong protection, many travelers choose to get it once to avoid any border-crossing issues throughout Africa. You should receive the dose at least 10 days before arrival for the certificate to be valid.