First-Class Mail
Mail in 1–5 Business Days
First-Class Mail® service is an affordable and easy way to send envelopes and postcards. First-Class Mail Forever® stamps cost $0.68 (the current 1 oz price) and will never expire, even if the First-Class™ postage rate goes up.
To send packages, see USPS Ground Advantage™ service.
Features & Pricing
- Mail delivered in 1–5 business days
- Our best-priced for items up to 13 oz
- Eligible for Delivery Confirmation™ services such as Certified Mail®
- One price for up to 3.5 ounces with commercially priced letters and cards
- Prices based on shape and weight
Letters
- Standard-sized, rectangular envelope stamps start at $0.68.
- Square, oversized, or unusually shaped envelope stamps start at $1.12.
Postcards
- Standard-sized, rectangular postcard stamps start at $0.53.
- Oversized postcards need letter stamps, which start at $0.68.
Large Envelopes
- Large envelopes (flats) start at $1.39.
Weight, Size, & Shape Requirements
- Maximum weight for First-Class Mail letters is 3.5 oz; for large First-Class Mail envelopes, the maximum weight is 13 oz.
- All postcards and envelopes (or flats) must be rectangular, otherwise an additional charge may apply. Additional size restrictions apply depending on the type of mailpiece you're sending.
Additional Charges for Irregular Mailpieces & Envelopes
Nonmachinable Envelopes
Unusually shaped mail, like square or vertical envelopes, lumpy envelopes, rigid envelopes, and mail with clasps, string, or buttons, must be hand-canceled. They are charged a nonmachinable surcharge even if they weigh less than 1 oz.
Large Mailpieces
Letters that exceed the First-Class standard envelope maximum length, height, or thickness are charged large envelope (flat) prices.
Large Envelopes (flats) Treated as Small Packages
Large First-Class envelopes (flats) that exceed maximum dimensions or are rigid, non-rectangular, or not uniformly thick are charged package prices and shipped with USPS Ground Advantage.
TIP: Use the USPS® Price Calculator tool to calculate your domestic postage costs. You’ll need to know your mailpiece’s weight, shape, and size measurements.