Let's avoid that from happening! To benefit from the maximum amount of postal discounts, make sure to leave us the blank 2.5" x 4" address area the USPS asks for and a blank 1.25 x 1.25 area in the top right corner for the postal indicia. That's it! As you can see above, USPS requires a 1.25” X 1.25” indicia area and a 2.5" x 4" addressing area. In most cases this is not a problem as the print area is much larger than the indicia and addressing area combined; however, when printing on 4” X6” postcards a significant portion of the card must be reserved for addressing and indicia. If your artwork doesn’t meet the USPS Automation criteria, you will be charged USPS non-automation rates. Your pricing will be adjusted if your artwork fails Automation. First Class Presorted automation on a 4" x 6" is 0.305 cents. If your design does not meet automation design criteria, the postage will be 0.335 cents/each. First Class Presorted automation on other sizes up to 6" x 11" is 0.455 cents.