Aspect Ratio
The Aspect What? Aspect ratio is the length of the postcard divided by the height of the postcard. This result is the aspect ratio. In order to receive lower automation compatible postage rates for your postcards, the aspect ratio of the postcard must be 1.3 or greater. For instance: postcards measuring 4.25” x 6” would have an aspect ratio of 1.4 which would qualify the piece for lower postage rates. Now, let’s look at a postcard with the dimensions of 4.25” x 5.5”. The aspect ratio of 5.5 divided by 4.25 is only 1.29 and, as a result, will not qualify for the lower automation compatible postage rates.

Consider The Postage Cost In Addition To The Printing Cost!
When designing your postcard, it pays to make the size a major consideration. Otherwise, you could end up paying a lot more in postage to mail them. The most economical way to print a postcard is to run four 4.25” x 5.5” postcards on an 8.5” x 11” sheet. Due to the aspect ratio, your mail piece could result in higher postage rates in comparison to paying slightly more for printing a 4” x 6” postcard.