How much does it cost to mail a 1.2 ounce letter?

As of October 2023, mailing a standard letter weighing up to 1 ounce within the United States costs $0.66 with a First-Class stamp. For a letter weighing 1.2 ounces, you would need to pay an additional ounce rate, which totals approximately $0.88. Prices may vary if you're using different services or sending internationally. Always check the latest rates on the USPS website for the most accurate information.