"Postage costs" refers to the amount of money required to send a letter or package through the mail. It represents the fee charged by the postal service for delivering the item to its destination. Full definition
U.K. and E.U. readers may order the general trade paperback from Amazon, manufactured in Europe for faster delivery and lower postage costs. (unlimitedpublishing.com)
That way, you won't have to worry about higher postage costs when mailing a 1 - ounce first - class letter (regardless of future price increases). (efile.com)