Invitations should be ordered when you have all the details of your wedding set… place, time of ceremony and reception, as well as your guest list. Plan to place your invitation order at least 3-4 months in advance, some companies may require 4-6 months. Especially, if you are ordering custom made invitations or handmade invitations and coordinating ensembles. Depending on the intricacy of your design and because they are not mass produced, but rather assembled one by one it can take anywhere f.