The U.S. Postal Service has implemented a postage rate increase for all mail classes including First Class Mail®, Priority Mail and Express Mail along with many special services.
Here is a summary of the 2013 USPS postage rate increase:
First Class Letters (1 oz.) increase by one cent to $0.46 from $0.45. Each additional ounce will cost an extra $0.20 (no change)
First Class Flats (1 oz.) increase by two cents to $0.92 from $0.90. Each additional ounce will cost an extra $0.20 (no change)
Postcard rates increase by one cent to $0.33 from $0.32
Priority Mail Commercial Base (online postage) rates increase by an average of 6.3% and will start at $5.05 (previously at $4.90)