USPS First Class Mail

How Does First-Class Mail® Work?

After you’ve sealed and addressed your item, you must check its dimensions before trying to send it through First-Class Mail®. USPS has size restrictions for letters and packages sent with this service as shown below:

*Rates listed are discounted rates for online purchase available through Stamps.com

You can attach stamps to large envelopes being sent through First-Class Mail® as long as you’ve met USPS’s weight restrictions. It costs $1.50 to send the first ounce of a large envelope. Letters that can’t be sent through the Post Office’s automated machines have a $0.28 postage surcharge; the shape of the letter determines whether or not it is subject to this surcharge or not. Find out more about how shape affects the price of First-Class Mail®.

You can purchase additional services for your First-Class Mail® item. Certified Mail® is available for all pieces of mail sent through First-Class Mail®. If you are sending a postcard, Registered Mail, Return Receipt, insurance, restricted delivery, and COD are not available.

Sending First-Class Mail® with Stamps.com Saves Time and Money

Send First Class Mail Online: Stamps.com customers have an advantage when sending First-Class Mail®. The online postage company is one of the only PC Postage vendors that allow you to print first-class postage online. This includes First Class International Mail which is hugely popular with eBay sellers. Other vendors such as Click-and-Ship and PayPal require you to upgrade to a higher, more expensive mail class such as Priority Mail.

Print Exact Postage: Stamps.com also gives you the flexibility to print the exact postage amount on every stamp, whether it be one ounce or five ounces. Additionally, we offer free software upgrades each year when the USPS performs their annual rate adjustment, ensuring that you’ll never need one or two cents postage stamps again.