Yes, you can change the number of tickets purchased through the website up to 4 days before your arrival. This can only be done by cancelling the entire booking via the link in the confirmation email. You will receive a refund, but we do charge €2.50 per modified booking. Afterwards, you can book the correct number of new tickets via www.keukenhof.nl. You can always add extra tickets via www.keukenhof.nl, as long as tickets are still available for the selected time slot.