• BookBoon
    BookBoon provides textbooks in microeconomics, macroeconomics and a variety of other related fields. The books can be downloaded for free but do contain some minimal advertising.
  • Open Textbook Library
    From the University of Minnesota, this collection of e-textbooks includes books on economic analysis, microeconomics, and more. The books are openly licensed, complete, and suitable for adoption. There is also a paid option for students who want to get a print edition.