👉 "Fourth Fare" is a term used in the United States Postal Service (USPS) to describe the cost of mailing a letter or package. It is calculated based on the weight and size of the item, as well as the distance it needs to be sent. The "fourth fare" is charged for each additional ounce of weight above the initial 3 pounds. This is in contrast to the standard postage rate which is calculated at the base rate of 15 cents per ounce.
