Oh where do we start? Most postcards are designed to be mailed*, so we’ll begin with USPS specifications. The United States Post Office divides mail into two major categories: “letter” size and “flat” size. Letter size mail can be as small as 3.5” x 5” and as large as 6.25” x 11.5”. Think of a batch of mail you could hold in your hand – they’re letter size. If a postcard is larger on any one dimension, for example 8.5” x 11”, it is considered “flat” mail. Picture a couple of magazines. You really can’t hold them straight in your one hand, but you can hold them if they also rest on your arm – they’re “flats.”
Knowing these size limitations is important, since the postage calculations are different for each group. Marketing postcards are usually sent Standard Mail (as opposed to First Class Mail) and the postage for letter size standard mail is calculated by a piece rate, according to the correctness of the address and the number of pieces to a given area. Flat size pieces use a similar set of calculations but also include a weight factor.
Having said all that, let’s concentrate on postcards that will be sent as letter size standard mail. As noted above, you can work with anything from 3.5” x 5” (way too small for marketing) to 6.25” x 11.5” (that’s a lot of real estate), but the most common sizes we print are 5” x 7”, 5.5” x 8.5” and 6” x 9”. Because paper comes in stock sizes to fit our presses, these sizes can be printed four, five and six on a sheet, making them efficient and cost effective.
If you don’t mind paying a few dollars more for your mailing you may want to consider a “flat” size mail piece. Two cost effective sizes are 8.5” x 11” and its twin double, 11” x 17” with a vertical fold (finished size is same 8.5” x 11”).
*Mail-able postcards also have cousins called door hangers and rack cards. The former is self-explanatory and the latter is basically a postcard without a mailing panel – a postcard designed to sit in a rack for impulse pickup rather than mailed. Door hangers are generally 4.25” x 11” and rack cards 4.25” x 9”. Other than that, most of the concepts on this web site are applicable.
You can design your own rack cards at www.ezdiscountprinting.com/products/rackcards and door hangers at www.ezdiscountprinting.com/products/doorhangers.