If you choose a postcard style reply card instead of an envelope response card, you don’t have to match up the dimensions to an envelope size. You just have to make sure the postcard dimensions are within the postcard guidelines given by the postal service. At the time of this posting, the postcard length must be between 5 and 6 inches. The height must be between 3.5 and 4.25 inches. The paper must also be between .007 and .016 inches thick.
We highly recommend 4.25 x 5.5 inches as your postcard style response card size. This size is within the postal service guidelines. 4 postcards of this size also fit perfectly on an 8.5 x 11 sheet of paper so there is no waste.
Check out our postcard page for more information about the benefits of a reply card postcard.