Child visitors The child visitor category is for children aged under 18 years old who want to come to the UK for up to 6 months (or up to 12 months if they are accompanying an academic visitor). This includes children who want to study in the UK for up to 6 months. If a child wants to study here for more than 6 months, they must apply under Tier 4 (Child). You can find more information in the Studying in the UK section.