* Postcards: Flat rate of $0.34 per card.
* Letters (1 ounce or less): Flat rate of $0.55 per letter.
* Letters (over 1 ounce): $0.55 for the first ounce and $0.27 for each additional ounce.
* Large envelopes (flats): $1.00 for the first ounce and $0.55 for each additional ounce.
* Packages: Pricing based on weight and dimensions.
Special services:
* Priority Mail: Starts at $8.95 for a flat rate envelope and $9.10 for a small flat rate box.
* Express Mail: Starts at $26.95 for a flat rate envelope and $28.95 for a small flat rate box.
* Certified Mail: Add $3.99 to the postage price.
* Registered Mail: Add $4.35 to the postage price.
* Signature Confirmation: Add $2.90 to the postage price.
* Insurance: Available for packages up to $5,000 in value.
Weight limits:
* Postcards: No weight limit.
* Letters: 3.5 ounces maximum.
* Large envelopes (flats): 1 pound maximum.
* Packages: 70 pounds maximum.
Dimensions limits:
* Postcards: Maximum length of 6 inches and maximum width of 4.25 inches.
* Letters: Maximum length of 12 inches and maximum height of 6 inches.
* Large envelopes (flats): Maximum length of 15 inches and maximum width of 12 inches.
* Packages: Maximum length of 108 inches (combined length and girth).
For more information, please visit the USPS website.