What's the maximum ratio for a Family rate Merlin Annual Pass? We require a minimum 3 people and a maximum of 2 adults aged 16 and over to purchase our family passes. Related articles Can I still take advantage fo the family rate, with my party being 6 or more? I'm a single parent, can I take advantage of the Family Rate? Do we have to be related to take advantage of the Family Rate? What happens when my child becomes 16 years old and is classed as an adult? What is a Merlin Annual Pass Plus?