For refunds on pre-booked tours we ask you to give at least 7 days notice.  If deposits have been made to other parties, for example, for securing your event space, a full refund may not be possible.  It's probably best to give us a call to discuss.  If you are unable to make it on the day we will not be able to offer a refund but we may be able to give you credit or transfer your booking to another date.