1st class mail size
In the United States, the size requirements for First-Class Mail are as follows:
Length: The length of a First-Class Mail piece must not exceed 11.5 inches (29.2 cm).
Width: The width of a First-Class Mail piece must not exceed 6.125 inches (15.6 cm).
Thickness: The thickness of a First-Class Mail piece must not exceed 0.75 inches (1.9 cm).
Maximum Weight: The maximum weight for a First-Class Mail piece is 3.5 ounces (99 grams).
Size Examples:
- Envelopes: 3.5 x 6.125 x 0.25 inches (8.9 x 15.6 x 0.6 cm)
- Letters: 3.5 x 6.125 x 0.25 inches (8.9 x 15.6 x 0.6 cm)
- Postcards: 3.5 x 5.5 x 0.007 inches (8.9 x 14 x 0.2 cm)
- Greeting cards: 5 x 7 x 0.25 inches (12.7 x 17.8 x 0.6 cm)
Special Considerations:
- If your piece is larger than the maximum size, you can use a larger envelope or package, but you'll need to pay a higher postage rate.
- If your piece is irregularly shaped, you can use a special "flat" rate envelope or package, but you'll need to pay a higher postage rate.
- If your piece is a large or heavy package, you may need to use a different type of mail service, such as Priority Mail or Parcel Post.
Remember to always check with the United States Postal Service (USPS) for the most up-to-date information on First-Class Mail size and weight requirements.