If you ship books using media mail, be aware that a postage rate increase will become effective Sunday, May 31. The update, originally scheduled for April 26, was delayed due to corrections mandated by the Postal Regulatory Commission. Some of the categories included in the rate increase are certified mail, return receipts, registered mail, media mail and library mail.
Although the 1st Class 1 oz. letter rate remains at 49 cents, the extra ounce rate for letters and flats will increase from 21 cents to 22 cents. (The discount on metered letters will drop from 1 cent to .5 cent, so a 1st Class 1 oz. metered letter will increase from 48 cents to 48.5 cents.)