section_path: Types/Letters/First-Class
section_name: First-Class
paragraph_text: First-Class
  
  First-Class Mail in the U.S. includes postcards, letters, large envelopes (flats), and small packages, providing each piece weighs 13 ounces (370 g) or less. Delivery is given priority over second-class (newspapers and magazines), third class (bulk advertisements), and fourth-class mail (books and media packages). First-Class Mail prices are based on both the shape and weight of the item being mailed. Pieces over 13 ounces can be sent as Priority Mail. As of 2011 42% of First-Class Mail arrived the next day, 27% in two days, and 31% in three. The USPS expected that changes to the service in 2012 would cause about 51% to arrive in two days and most of the rest in three. The Canada Post counterpart is Lettermail.
  
  The British Royal Mail's 1st Class, as it is styled, is simply a priority option over 2nd Class, at a slightly higher cost. Royal Mail aims (but does not guarantee) to deliver all 1st Class letters the day after posting.
  
  In Austria priority delivery mail is called Prio, in Switzerland A-Post.