The United States Postal Service will change prices for Priority Mail Services on Sunday, September 7. These changes will affect all customers who mail over-sized large envelopes, flat rate envelopes, flat-rate boxes and packages. The USPS is introducing substantial reductions to attract customer who ship parcels by ground in the six to 20 lb range.
The new rates only apply to Priority Mail. The January 2014 rates for First Class Mail, Standard Mail, Standard Post, Media Mail, Library Mail, Priority Mail Express and International mail will not change.