What is the minimum letter size to mail

In the United States, the minimum letter size to mail is typically considered to be a standard #10 envelope, which measures 3.5 inches (8.9 cm) high, 6.125 inches (15.6 cm) long, and 0.007 inch (0.18 mm) thick. This size envelope is commonly used for sending standard letters, bills, and other correspondence.

However, the United States Postal Service (USPS) does not have a specific minimum size requirement for letters. As long as the envelope is rectangular in shape and meets the following criteria, it can be mailed:

  1. The envelope must be at least 3.5 inches (8.9 cm) high and 5 inches (12.7 cm) long.
  2. The envelope must be no more than 12 inches (30.5 cm) high and 15 inches (38.1 cm) long.
  3. The envelope must be no more than 0.75 inch (1.9 cm) thick.

It's worth noting that if you're sending a letter that is larger than a standard #10 envelope, you may need to use a larger envelope or a package, which may require additional postage and handling.

Here are some examples of minimum letter sizes for different types of mail:

Keep in mind that these are general guidelines, and the USPS may have specific requirements for certain types of mail, such as packages or oversized items. It's always a good idea to check with your local post office or the USPS website for specific guidelines on mailing sizes and requirements.