LETTERSHOP SERVICES - USPS Sorting

United States Postal Service mail classes include: First, Periodical, Standard, and Package Services (formerly 1st, 2nd, 3rd/Bulk and 4th, respectively).

Each class has it's strengths and weaknesses.  Your time frame and project parameters will often dictate the class to use.  Some mailings, such as bill statements, are required by Federal law to be submitted under First Class.

Ask your sales representative what classification is appropriate and beneficial for your project.