Postcards are an inexpensive way to send a quick greeting or a marketing message. Not only is the postage cheaper for a postcard, but the absence of an envelope makes the materials cheaper as well. This lower cost coupled with the fact that a consumer is more likely to read a postcard’s message prior to throwing it out, makes them a wise choice for direct marketing. In order to qualify as a postcard and get the lower rate, however, it must be within certain size limits and of a specific shape.
In the US, first class postage for a postcard is about 40% less than first class postage for a letter. Postcards for personal use are typically sent using this standard first class postcard rate. A bulk or automated rate is available for sending a large volume, and it reduces the cost of sending the card even further.
In order for a piece of mail to qualify as a postcard, it must meet several requirements set by the United States Postal Service. Postcard size is an important requirement for any piece of mail being sent with a first class postcard stamp. If the size requirements are not met for a postcard, the item may not be delivered, as postcards do not always include a return address.
The U.S. Postal Service has the following requirements for postcards sent using a postcard rate:
Postcards must be at least 3.5 inches (8.89 cm) high, 5 inches (12.7 cm) wide and 0.007 inches (0.018 cm) thick.
They can be no larger than 4.25 inches (10.8 cm) high, 6 inches (15.2 cm) wide and 0.016 inches (0.041 cm) thick.
The postcard must be rectangular in shape.
It cannot contain any stickers or attachments that make it larger or thicker than the above size.
A postcard size or shape outside of the above dimensions can be sent via the U.S. Postal Service, it simply requires a more expensive letter stamp for mailing. When in doubt, the mailer can use a letter stamp or ask the local Post Office the amount of postage needed. A good rule of thumb to follow is that a postcard must be 0.5 inch (1.27 cm) taller and at least as wide and as thick as an index card.
Postcards sent with an automation or bulk rate have even more stringent requirements for size and shape. These requirements are available from a local post office, who can help you determine if the postcard meets the specifications for automation rates. Pre-stamped postcards that conform to the postal requirements are also available for purchase directly from the post office.