On January 22, 2012 the U.S. Postal Service® will implement a postage rate increase for all mail classes including First Class Mail®, Priority Mail and Express Mail along with many special services.

Summary of the 2012 USPS postage rate increase:

• First Class Letters (1 oz.) will increase by one cent to $0.45 from $0.44. Each additional ounce will cost an extra $0.20 (no change)
• First Class Flats (1 oz.) will increase by two cents to $0.90 from $0.88. Each additional ounce will cost an extra $0.20 (no change)
• Postcard rates will increase by three cents to $0.32 from $0.29
• Priority Mail retail rates will increase by an average of 3.2% and will start at $5.20 (previously at $5.10)
• Express Mail retail rates will increase by an average of 4.4% and will start at $12.95 (previously at $12.85)
• Parcel Post rates will start at $5.20 (previously at $5.10)
• Media Mail rates will start at $2.47 (previously at $2.41)

Source: Stamps.com