Effective January 22, 2017 the cost of a first class (1) ounce letter sent through the United States Post Office increased two cents from $0.47 to $0.49 for letters mailed within the United States. Reversing the $0.2 price drop from $0.49 to $0.47 effective April 10, 2016. Any extra ounce(s) remain subject to a fee of $0.21 per added ounce. These fees will continue to apply and extend for an indeterminate period of time. The current `017 $0.49 is the exact amount that went into effect January 26, 2014 as the result of a $0.03 increase from $0.46.