Can one stamp mail a letter

In the United States, the answer is generally no, you cannot use a single stamp to mail a letter. Here's why:

• The United States Postal Service (USPS) requires a minimum postage of $0.55 for a standard, one-ounce letter (1 oz) to be mailed within the United States. This is the cost of a First-Class Mail stamp.
• If your letter weighs more than 1 oz, you'll need to use additional postage, which can be calculated using the USPS's online postage calculator or by visiting a post office.
• If you're mailing a letter internationally, the postage cost will depend on the destination, weight, and size of the letter. You can use the USPS's online postage calculator or consult with a postal worker to determine the correct postage.

However, there are some exceptions where you might be able to mail a letter with a single stamp:

• If you're mailing a letter to a nearby zip code or within the same state, you might be able to get away with using a single stamp. But this is not guaranteed, and you could still be charged additional postage if the letter is heavier or larger than expected.
• If you're using a special type of postage, such as a Forever Stamp, which is valid for First-Class Mail Forever letters weighing up to 1 oz, you might be able to mail a letter with a single stamp. However, this only applies to letters sent within the United States.

To avoid any potential issues or additional charges, it's always best to check the USPS website or consult with a postal worker to determine the correct postage for your letter.