It’s very important that you should understand the postal rules applicable to your state before you start promoting your business through postcard marketing. Be sure, that your postcard is able to reach your desired target audience otherwise you would just waste your time and money. Here, are rules and regulations of postcard mailing set by USPS, for US residents.


There are two types of postcards long and short, standard thickness for both postcards should be 3/16”, 5” mm. There are extra charges for oversize category. Get the weight limit of postcards. Standard maximum weight for both long and short postcards is set to 100 grams.

Size and weight

You should also consider the size of postcards if you exceed the required limit with only one millimeter it can make a big difference in your overall cost. Standard rectangular postcards have following dimensions: (height) 3-1/2” * (length) 5” * (thickness) 0.007” to (height) 4-1/4” * (length) 6” * (thickness) 0.016”.


Design the postcard in a way that you leave enough space for stamps and address line. If you don’t leave that space you may have to sacrifice your postcard design after stamp and mailing address has been posted. You should not write anything on the postage area on the card except mailing address.

Barcode area

There is a barcode area located 5/8” from the bottom of postcard – where mailing address is printed on the back side of postcard. You should leave this area empty for barcode. You may not use barcode yourself but the post office will put postcard sticker on this area of postcard.

Printing service

Find an expert or professional printing company that offer different packages. Their package may include printing plus mailing service at low rates. For the bulk of postcards, printing companies offer lowest costs of printed and mailed postcards. Several printing companies are following USPS postal rules. So, always look for the legitimate and credible printing company.

Thus, these are some simple rules to follow before you decide about your postcard designs and materials. In order to save your money you should follow all these regulations otherwise you may have to pay extra charges on each of your postcard that can make a big difference in cost. It is one of the cost-effective marketing tool only if you follow the guidelines. Make sure, you have read all guidelines precisely to avoid money and time wastage.



Stan Coyle has 25 years experience in Direct Mail marketing. He has taught seminars from New York to London and has settled in Tampa, Florida for a semi-retirement of fishing and relaxation. Not being able to leave work alone, he contributes to the success of postcard marketing customers all over the U.S. with his work at can help you with your Every Door Direct Mail marketing postcard programs. We have helped thousands of businesses with their postcard marketing and we are experts in the Every Door Direct Mail program.