Every year you can expect prices on shipping and postage to increase. In 2018, postal services are projected to raise anywhere from 2%-3%. The USPS will raise rates for both market-dominant mail and competitive mail on January 21, 2018.
The new increased prices will be filed with the Postal Regulatory Commission in October. Purpose changes include raising the Forever stamp from 49 cents to 50 cents. USPS has to stick with the current inflation based cap, but changes will affect competitive mail rates which are popular with small and medium online sellers.
It's not just USPS that could be raising their rates for First Class and Priority Mail. January is a traditional time for UPS and FedEx to announce new increased prices.