Because we only use natural ingredients, and no chemical preservatives, they do have a shorter shelf life than supermarket chocolates. And because your box will most probably contain different chocolates that have been produced at different times with different ingredients, that too factors into how long your chocolates will last.
Your box will have a date stamped on the bottom. That is the date when at least one of the chocolates inside will reach its Best Before date. As a rule, chocolates containing chocolate and dairy ganaches inside have a shorter shelf life, and those without dairy will last longer.
Treat them well, keep them in a cool place - not the fridge.