The U.S. Postal Service announced last October that the following price changes will take effect on January 27, 2019:

First class letter postage increase from 50 cents to 55 cents.

Additional ounces on letters actually decreases from 21 cents to 15 cents.

The price of sending postcards remains at 35 cents.

Regular flat rate envelope increases from $6.70 to $7.35.

about.usps.com/newsroom/national-releases/2018/pr18_086.htm