Special Standard Mail & Library Mail - (Book Rate)
Weight Not Over 
Single-Piece
5-Digit
1 pound $1.13 $.64
2 pounds $1.58 $1.09
3 pounds $2.03 $1.54
4 pounds $2.48 $1.99
5 pounds $2.93 $2.44
6 pounds $3.38 $2.89
7 pounds $3.83 $3.34
each addt'l pound $.28 $.28
Insurance is $.85 for $.01 to $50; $1.80 for $50.01-$100
 
Priority Mail
Weight Not Over
Single-Piece
1 pound $3.20
2 pounds $3.20
3 pounds $4.30
4 pounds $5.40
5 pounds $6.50
For heavier packages  see USPS website
 
  USPS Descriptions of Bound Printed Matter and Special Standard Mail

  Bound printed matter
  must weigh at least 1 pound but not more than 15 pounds and must:
  a. Consist of advertising, promotional, directory, or editorial material (or any combination of such material).
  b. Be securely bound by permanent fastenings such as staples, spiral binding, glue, or stitching. Looseleaf binders and similar
  fastenings are not considered permanent.
  c. Consist of sheets of which at least 90% are imprinted by any process other than handwriting or typewriting with words,
  letters, characters, figures, or images (or any combination of them).
  d. Not have the nature of personal correspondence.
  e. Not be stationery, such as pads of blank printed forms.


  Special Standard Mail
  may be up to 70 pounds and is:
  Generally used for books (at least eight pages), film (16 mm or narrower), printed music, printed test materials, sound
  recordings, play scripts, printed educational charts, loose-leaf pages and binders consisting of medical information, and
  computer-readable media.

  When we send our packages "book rate" they are being sent Special Standard Mail
  (this includes previous categories of book rate as well as library rate).

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